Build fix for BIND 9.13.4 on NetBSD

Description

BIND 9.13.4 fails to build on NetBSD 8.0 for a couple of reasons:

• The newish pthread-using module is not adapted to NetBSD; one function is missing, another has a different way of setting up the cpuset_t, and a third has an extra arg.

• The configure.ac script can be simplified to be the same as for FreeBSD and OpenBSD; it does not work as is when using libtool because ld doesn't recognize the -pthread flag when building in bin/tests/system/dyndb/driver, ref.

   libtool: link: ld -Bshareable -x -o .libs/sample.so .libs/db.o .libs/driver.o .libs/instance.o .libs/lock.o .libs/log.o .libs/syncptr.o .libs/zone.o  -L/usr/lib -L/usr/pkg/lib ../../../../../lib/dns/.libs/libdns.so /usr/local/src/bind-9.13.4/lib/isc/.libs/libisc.so -lgssapi ../../../../../lib/isc/.libs/libisc.so -lcrypto /usr/pkg/lib/libxml2.so -lz -llzma -lm -pthread  -Wl,-rpath -Wl,/usr/local/lib -Wl,-rpath -Wl,/usr/pkg/lib
   ld: unrecognized option '-pthread'
   ld: use the --help option for usage information

Request

Apply the diff which is attached below, or something along these lines.bind-9.13.4.diff

Links / references