Merge pull request #20711 from guzhongyan/mgr-nodels

mon: 'node ls' mgr support

Reviewed-by: John Spray <john.spray@redhat.com>
Reviewed-by: Kefu Chai <kchai@redhat.com>

diff --cc qa/workunits/cephtool/test.sh
Simple merge

diff --cc src/mon/MonCommands.h
Simple merge

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