ocfs2: update seq_file index in ocfs2_dlm_seq_next

The following INFO level message was seen:

seq_file: buggy .next function ocfs2_dlm_seq_next [ocfs2] did not
update position index

Fix:
Update *pos (so m->index) to make seq_read_iter happy though the index its
self makes no sense to ocfs2_dlm_seq_next.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Wengang Wang <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: Wengang-oracle

fs/ocfs2/dlmglue.c

@@ -3110,6 +3110,7 @@ static void *ocfs2_dlm_seq_next(struct seq_file *m, void *v, loff_t *pos)
 	struct ocfs2_lock_res *iter = v;
 	struct ocfs2_lock_res *dummy = &priv->p_iter_res;
 
+	(*pos)++;
 	spin_lock(&ocfs2_dlm_tracking_lock);
 	iter = ocfs2_dlm_next_res(iter, priv);
 	list_del_init(&dummy->l_debug_list);