osd/PG: only correct filestore collection bits on load

osd/PG: only correct filestore collection bits on load

PG::update_store_with_options() is called on load *and* when the pool
properties change, but if we only need to fix bits right at load time.
More importantly, but doing a second check on pool change, we may race
with a previously queued collection create that is not yet readable via
filestore, try to (synchronously) set the property again, and deadlock.

Fixes: http://tracker.ceph.com/issues/19541
Signed-off-by: Sage Weil <sage@redhat.com>