Merge pull request #3503 from ceph/wip-pg-reqids

osd: index PGLog with optional extra_reqids in each log entry

Reviewed-by: Samuel Just <sjust@redhat.com>
Reviewed-by: Wang, Zhiqiang <zhiqiang.wang@intel.com>

diff --cc src/osd/ReplicatedPG.cc
Simple merge

diff --cc src/osd/osd_types.cc
Simple merge

diff --cc src/osd/osd_types.h
Simple merge