Merge pull request #6665 from trociny/wip-librbd-journal

rbd: journal: configuration via conf, cli, api and some fixes

Reviewed-by: Josh Durgin <jdurgin@redhat.com>

diff --cc src/common/config_opts.h
Simple merge

diff --cc src/include/rbd/librbd.h
Simple merge

diff --cc src/journal/Journaler.h
Simple merge

diff --cc src/librbd/ImageCtx.h
Simple merge

diff --cc src/librbd/JournalReplay.h
Simple merge

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