Make DocBook sources namespaced again

Every DocBook source document can be namespaced (DocBook 5) or
non-namespaced (DocBook 4).  The set of XSL stylesheets used for
producing an output document can also be namespaced or non-namespaced.
Namespaced source documents should be used with namespaced stylesheets
and non-namespaced source documents should be used with non-namespaced
stylesheets.  However, both stylesheet flavors contain processing rules
which allow them to be used interchangeably for any type of source
document.

Unfortunately, these processing rules became broken in version 1.79.1 of
the stylesheets, which means that non-namespaced source documents can no
longer be correctly transformed into man pages using namespaced
stylesheets and vice versa.  This problem was fixed upstream [1], but no
released version of the XSL stylesheets contains that fix yet.

Back in 2016, this problem was reported as RT #43831 and allegedly fixed
in commit 1b8ce3b3.  However, that fix
only helped for the non-namespaced version of the stylesheets - while
also breaking man page generation for the namespaced flavor.

Since using namespaced DocBook sources is the current best practice
(DocBook 5), make BIND DocBook sources namespaced again.  When using
version 1.79.1 or 1.79.2 of the XSL stylesheets, care must be taken to
ensure namespaced stylesheets are used for generating BIND
documentation.

[1] https://github.com/docbook/xslt10-stylesheets/issues/109
84 jobs for !4440 with 2310-make-docbook-sources-namespaced-again in 15 minutes and 14 seconds (queued for 8 seconds)
detached
Status Job ID Name Coverage
  Precheck
passed #1327194
amd64 linux
autoreconf

00:00:22

passed #1327196
amd64 linux
clang-format

00:00:15

passed #1327197
amd64 linux
coccinelle

00:01:03

passed #1329735
linux amd64
danger

00:00:15

passed #1327195
amd64 linux
misc

00:00:22

failed #1327198
amd64 linux
danger

00:00:22

 
  Build
passed #1327213
amd64 linux
clang:asan

00:05:01

passed #1327218
amd64 linux
clang:buster:amd64

00:02:19

passed #1327220
amd64 libvirt
clang:freebsd11:amd64

00:01:52

passed #1327221
amd64 libvirt
clang:freebsd12:amd64

00:01:41

passed #1327222
amd64 libvirt
clang:openbsd:amd64

00:03:53

passed #1327215
amd64 linux
clang:tsan

00:02:53

passed #1327199
amd64 linux
gcc:alpine3.12:amd64

00:01:39

passed #1327212
amd64 linux
gcc:asan

00:03:43

passed #1327205
amd64 linux
gcc:buster:amd64

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passed #1327201
amd64 linux
gcc:centos6:amd64

00:01:42

passed #1327200
i386 linux
gcc:centos6:i386

00:01:47

passed #1327202
amd64 linux
gcc:centos7:amd64

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passed #1327203
amd64 linux
gcc:centos8:amd64

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passed #1327209
amd64 linux
gcc:fedora33:amd64

00:02:27

passed #1327211
amd64 linux
gcc:focal:amd64

00:02:09

passed #1327216
amd64 linux
gcc:mutexatomics

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passed #1327217
amd64 linux
gcc:noatomics

00:02:02

passed #1327207
amd64 linux
gcc:out-of-tree

00:01:48

passed #1327219
amd64 linux
gcc:pkcs11

00:02:19

passed #1327206
amd64 linux
gcc:sid:amd64

00:04:00

passed #1327204
amd64 linux
gcc:stretch:amd64

00:02:05

passed #1327214
amd64 linux
gcc:tsan

00:02:27

passed #1327208
amd64 linux
gcc:tumbleweed:amd64

00:02:10

passed #1327210
amd64 linux
gcc:xenial:amd64

00:01:56

passed #1327224
amd64 windows
msvc:windows:amd64

00:01:09

passed #1327223
amd64 linux
nolibtool:sid:amd64

00:03:09

 
  Unit
passed #1327238
amd64 linux
unit:clang:asan

00:01:10

passed #1327243
amd64 linux
unit:clang:buster:amd64

00:00:37

passed #1327245
amd64 libvirt
unit:clang:freebsd11:amd64

00:01:15

passed #1327246
amd64 libvirt
unit:clang:freebsd12:amd64

00:01:03

passed #1327240
amd64 linux
unit:clang:tsan

00:04:03

passed #1327225
amd64 linux
unit:gcc:alpine3.12:amd64

00:00:36

passed #1327237
amd64 linux
unit:gcc:asan

00:01:14

passed #1327231
amd64 linux
unit:gcc:buster:amd64

00:01:02

passed #1327227
amd64 linux
unit:gcc:centos6:amd64

00:00:43

passed #1327226
i386 linux
unit:gcc:centos6:i386

00:00:38

passed #1327228
amd64 linux
unit:gcc:centos7:amd64

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passed #1327229
amd64 linux
unit:gcc:centos8:amd64

00:00:35

passed #1327234
amd64 linux
unit:gcc:fedora33:amd64

00:00:31

passed #1327236
amd64 linux
unit:gcc:focal:amd64

00:00:39

passed #1327241
amd64 linux
unit:gcc:mutexatomics

00:00:35

passed #1327242
amd64 linux
unit:gcc:noatomics

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passed #1327244
amd64 linux
unit:gcc:pkcs11

00:00:37

passed #1327232
amd64 linux
unit:gcc:sid:amd64

00:00:30

passed #1327230
amd64 linux
unit:gcc:stretch:amd64

00:00:52

passed #1327239
amd64 linux
unit:gcc:tsan

00:04:56

passed #1327233
amd64 linux
unit:gcc:tumbleweed:amd64

00:00:40

passed #1327235
amd64 linux
unit:gcc:xenial:amd64

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passed #1327247
amd64 linux
unit:nolibtool:sid:amd64

00:00:51

 
  System
passed #1327261
amd64 linux
system:clang:asan

00:09:00

passed #1327266
amd64 linux
system:clang:buster:amd64

00:07:33

passed #1327268
amd64 libvirt
system:clang:freebsd11:amd64

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passed #1327269
amd64 libvirt
system:clang:freebsd12:amd64

00:08:14

passed #1327263
amd64 linux
system:clang:tsan

00:11:13

passed #1327248
amd64 linux
system:gcc:alpine3.12:amd64

00:07:46

passed #1327260
amd64 linux
system:gcc:asan

00:09:16

passed #1327254
amd64 linux
system:gcc:buster:amd64

00:08:05

passed #1327250
amd64 linux
system:gcc:centos6:amd64

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passed #1327249
i386 linux
system:gcc:centos6:i386

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passed #1327251
amd64 linux
system:gcc:centos7:amd64

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passed #1327252
amd64 linux
system:gcc:centos8:amd64

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passed #1327257
amd64 linux
system:gcc:fedora33:amd64

00:07:08

passed #1327259
amd64 linux
system:gcc:focal:amd64

00:07:20

passed #1327264
amd64 linux
system:gcc:mutexatomics

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passed #1327265
amd64 linux
system:gcc:noatomics

00:07:50

passed #1327267
amd64 linux
system:gcc:pkcs11

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passed #1327255
amd64 linux
system:gcc:sid:amd64

00:07:04

passed #1327253
amd64 linux
system:gcc:stretch:amd64

00:07:30

passed #1327262
amd64 linux
system:gcc:tsan

00:11:59

passed #1327256
amd64 linux
system:gcc:tumbleweed:amd64

00:07:14

passed #1327258
amd64 linux
system:gcc:xenial:amd64

00:06:50

passed #1327270
amd64 linux
system:nolibtool:sid:amd64

00:07:15

 
  Docs
passed #1327271
amd64 linux
docs

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  Postcheck
passed #1327275
amd64 linux
cppcheck

00:00:43

passed #1327272
amd64 linux
flake8

00:00:41

passed #1327276
amd64 linux
gcov

00:00:34

74.0%
passed #1327273
amd64 linux
pylint

00:00:41

passed #1327274
amd64 linux
scan-build

00:09:35