Merge PR #36204 into master

* refs/pull/36204/head:
	client: add command_lock support
	client: defer swapping the newmap to mdsmap
	client: try to grab the client_lock when needed
	client: clean up the client code

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

diff --cc src/client/Client.cc
Simple merge

diff --cc src/client/Client.h
Simple merge