fs: dlm: use free_con to free connection

This patch use free_con() functionality to free the listen connection if
listen fails. It also fixes an issue that a freed resource is still part
of the connection_hash as hlist_del() is not called in this case. The
only difference is that free_con() handles othercon as well, but this is
never been set for the listen connection.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

fs/dlm/lowcomms.c

@@ -1704,10 +1704,8 @@ int dlm_lowcomms_start(void)
 fail_unlisten:
 	dlm_allow_conn = 0;
 	con = nodeid2con(0,0);
-	if (con) {
-		close_connection(con, false, true, true);
-		kfree_rcu(con, rcu);
-	}
+	if (con)
+		free_conn(con);
 fail:
 	return error;
 }