Merge pull request #14436 from dachary/wip-19513-ceph-disk-device-class

ceph-disk,osd: add support for crush device classes

Reviewed-by: Sage Weil <sage@redhat.com>

diff --cc src/ceph-disk/ceph_disk/main.py
Simple merge

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

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

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