Fix exception path typo in app_queue.c try_calling().

(closes issue ASTERISK-20380)
Reported by: Jeremy Pepper
Patches:
      fix-local-channel-locking.patch (license #6350) patch uploaded by Jeremy Pepper


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@372624 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_queue.c

@@ -4543,7 +4543,7 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 				callattempt_free(tmp);
 				ao2_ref(cur, -1);
 				ao2_iterator_destroy(&memi);
-				ao2_unlock(&qe->parent);
+				ao2_unlock(qe->parent);
 				goto out;
 			}
 			datastore->data = dialed_interfaces;