crimson/osd/pg_recovery: only reset_pglog_based_recovery_op if complete

crimson/osd/pg_recovery: only reset_pglog_based_recovery_op if complete

ce4e9aaad, as part of the start_recovery_ops changed the call to
reset_pglog_based_recovery_op to occur unconditionally rather than only
if recovery has completed.

Note, this fix only restores the prior behavior.  There's actually still
a race here where a DeferRecovery could be processed between the call to
reset_pglog_based_recovery_op and the RequestBackfill or
AllReplicasRecovered being processed.

Introduced: ce4e9aaad8f2cafae24511fe1687c61dc41affc1
Related: https://tracker.ceph.com/issues/71267
Fixes: https://tracker.ceph.com/issues/70337
Signed-off-by: Samuel Just <sjust@redhat.com>