Merge PR #21080 into master

* refs/pull/21080/head:
	src: Added const references to various function parameters

Reviewed-by: Kefu Chai <kchai@redhat.com>
Reviewed-by: Patrick Donnelly <pdonnell@redhat.com>

diff --cc src/kv/RocksDBStore.cc
Simple merge

diff --cc src/mds/MDCache.cc
Simple merge

diff --cc src/mds/MDCache.h
Simple merge

diff --cc src/mgr/ActivePyModules.cc
Simple merge

diff --cc src/mgr/DaemonServer.cc
Simple merge

diff --cc src/mon/PGMap.cc
Simple merge

diff --cc src/os/ObjectStore.h
Simple merge

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

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

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

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