Merge pull request #37788 from tchaikov/wip-zbd

rpm,cmake: s/WITH_LIBZBD/WITH_ZBD/ and enable ZBD on demand

Reviewed-by: Josh Durgin <jdurgin@redhat.com>
Reviewed-By: Neha Ojha <nojha@redhat.com>

diff --cc CMakeLists.txt
Simple merge

diff --cc ceph.spec.in
Simple merge

diff --cc src/blk/CMakeLists.txt
Simple merge