ocfs2: Print message if user mounts without starting global heartbeat

In global heartbeat mode, the heartbeat is started by the user. This patch
prints an error if the user attempts to mount a volume without starting the
heartbeat.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>

fs/ocfs2/stack_o2cb.c

@@ -283,6 +283,8 @@ static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn)
 	/* for now we only have one cluster/node, make sure we see it
 	 * in the heartbeat universe */
 	if (!o2hb_check_local_node_heartbeating()) {
+		if (o2hb_global_heartbeat_active())
+			mlog(ML_ERROR, "Global heartbeat not started\n");
 		rc = -EINVAL;
 		goto out;
 	}