[DLM] res_recover_locks_count not reset when recover_locks is aborted

Red Hat BZ 213684

If a node sends an lkb to the new master (RCOM_LOCK message) during
recovery and recovery is then aborted on both nodes before it gets a
reply, the res_recover_locks_count needs to be reset to 0 so that when the
subsequent recovery comes along and sends the lkb to the new master again
the assertion doesn't trigger that checks that counter is zero.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>