The BIND 9 libraries are now internal-only, so remove isc-config.sh

The isc-config.sh script was introduced before pkg-config as is a purely
historical thing.  There are two reason for removal of isc-config.sh scripts:

a) The BIND 9 libraries are now meant to be used only from BIND 9, so there's no
   reason to provide convenience script to link with the libraries.

b) Even if that was not the case, we should and would replace the isc-config.sh
   with respective pkg-config (.pc) file for every library.
48 jobs for !2086 with 4-remove-isc-config.sh in 19 minutes and 16 seconds (queued for 4 seconds)
detached
Status Job ID Name Coverage
  Precheck
passed #265829
amd64 linux
🐞:sid:amd64

00:00:13

passed #265826
amd64 linux
autoconf

00:00:35

passed #265827
amd64 linux
autoreconf:sid:amd64

00:00:35

passed #265828
amd64 linux
misc:sid:amd64

00:00:22

 
  Build
passed #265840
amd64 linux
asan:sid:amd64

00:02:14

passed #265842
amd64 linux
clang:stretch:amd64

00:02:09

passed #265843
i386 linux
clang:stretch:i386

00:02:12

passed #265830
amd64 linux
docs:sid:amd64

00:01:11

passed #265839
amd64 linux
gcc:bionic:amd64

00:02:06

passed #265831
amd64 linux
gcc:centos6:amd64

00:02:41

passed #265832
amd64 linux
gcc:centos7:amd64

00:02:41

passed #265837
amd64 linux
gcc:fedora29:amd64

00:03:17

passed #265833
amd64 linux
gcc:jessie:amd64

00:01:32

passed #265835
amd64 linux
gcc:sid:amd64

00:02:40

passed #265836
i386 linux
gcc:sid:i386

00:02:01

passed #265834
amd64 linux
gcc:stretch:amd64

00:01:59

passed #265838
amd64 linux
gcc:xenial:amd64

00:02:06

passed #265845
amd64 linux
nolibtool:sid:amd64

00:02:08

passed #265844
amd64 linux
pkcs11:sid:amd64

00:01:43

passed #265841
amd64 linux
rwlock:sid:amd64

00:02:01

 
  Test
passed #265864
amd64 linux
system:asan:sid:amd64

00:09:25

passed #265862
amd64 linux
system:gcc:bionic:amd64

00:07:39

passed #265846
amd64 linux
system:gcc:centos6:amd64

00:07:26

passed #265848
amd64 linux
system:gcc:centos7:amd64

00:07:30

passed #265858
amd64 linux
system:gcc:fedora29:amd64

00:08:19

passed #265850
amd64 linux
system:gcc:jessie:amd64

00:07:22

passed #265945
amd64 linux
system:gcc:sid:amd64

00:06:24

passed #265856
i386 linux
system:gcc:sid:i386

00:07:48

passed #265852
amd64 linux
system:gcc:stretch:amd64

00:07:24

passed #265860
amd64 linux
system:gcc:xenial:amd64

00:07:13

passed #265871
amd64 linux
system:nolibtool:sid:amd64

00:08:19

passed #265869
amd64 linux
system:pkcs11:sid:amd64

00:07:50

passed #265866
amd64 linux
system:rwlock:sid:amd64

00:08:28

passed #265865
amd64 linux
unit:asan:sid:amd64

00:01:22

passed #265868
amd64 linux
unit:clang:stretch:amd64

00:00:59

passed #265863
amd64 linux
unit:gcc:bionic:amd64

00:00:48

passed #265847
amd64 linux
unit:gcc:centos6:amd64

00:00:50

passed #265849
amd64 linux
unit:gcc:centos7:amd64

00:01:02

passed #265859
amd64 linux
unit:gcc:fedora29:amd64

00:00:57

passed #265851
amd64 linux
unit:gcc:jessie:amd64

00:00:50

passed #265855
amd64 linux
unit:gcc:sid:amd64

00:01:06

passed #265857
i386 linux
unit:gcc:sid:i386

00:00:54

passed #265853
amd64 linux
unit:gcc:stretch:amd64

00:01:04

passed #265861
amd64 linux
unit:gcc:xenial:amd64

00:01:09

passed #265872
amd64 linux
unit:nolibtool:sid:amd64

00:01:16

passed #265870
amd64 linux
unit:pkcs11:sid:amd64

00:00:47

passed #265867
amd64 linux
unit:rwlock:sid:amd64

00:01:04

failed #265854
amd64 linux
system:gcc:sid:amd64

00:08:07