Merge pull request #9440 from dillaman/wip-16114

librbd: prevent error messages when journal externally disabled

Reviewed-by: Mykola Golub <mgolub@mirantis.com>

diff --cc src/librbd/internal.cc
Simple merge

diff --cc src/osdc/ObjectCacher.h
Simple merge

diff --cc src/test/librbd/exclusive_lock/test_mock_AcquireRequest.cc
Simple merge