provision: Add support for BIND 9.12.x

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

Autobuild-User(master): Andrew Bartlett <abartlet@samba.org>
Autobuild-Date(master): Fri Aug 10 05:36:19 CEST 2018 on sn-devel-144
