Merge pull request #6572 from liewegas/wip-crush-chooseleaf-stable

crush: add chooseleaf_stable tunable

Reviewed-by: Loic Dachary <ldachary@redhat.com>

diff --cc src/crush/CrushCompiler.cc
Simple merge

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

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

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