osd: Correction to #6690 change

Reorder sequence so min_size check is right
Remove redundant resize of backfill

Correction to 19cff890eb6083eefdb7b709773313b2c8acbcea

Signed-off-by: David Zafman <david.zafman@inktank.com>
osd: Remove redundant incompat feature

Signed-off-by: David Zafman <david.zafman@inktank.com>
osd: Config OSD when CEPH_FEATURE_OSD_ERASURE_CODES feature first seen

Set the OSD superblock CEPH_OSD_FEATURE_INCOMPAT_SHARDS and
notify the filestore through set_allow_sharded_objects() in that order.

Signed-off-by: David Zafman <david.zafman@inktank.com>
osd: Determine if compatibility is requried due to back level OSDs

Signed-off-by: David Zafman <david.zafman@inktank.com>