locking/debug: Fix debugfs API return value checks to use IS_ERR()

Update the checking of return values from debugfs_create_file()
and debugfs_create_dir() to use IS_ERR().

Signed-off-by: Atul Kumar Pant <[e-mail]>
Signed-off-by: Ingo Molnar <[e-mail]>
Acked-by: Waiman Long <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

kernel/locking/lock_events.c

···
 	struct dentry *d_counts = debugfs_create_dir(LOCK_EVENTS_DIR, NULL);
 	int i;
 
-	if (!d_counts)
+	if (IS_ERR(d_counts))
 		goto out;
 
 	/*
···
 	for (i = 0; i < lockevent_num; i++) {
 		if (skip_lockevent(lockevent_names[i]))
 			continue;
-		if (!debugfs_create_file(lockevent_names[i], 0400, d_counts,
-					 (void *)(long)i, &fops_lockevent))
+		if (IS_ERR(debugfs_create_file(lockevent_names[i], 0400, d_counts,
+					 (void *)(long)i, &fops_lockevent)))
 			goto fail_undo;
 	}
 
-	if (!debugfs_create_file(lockevent_names[LOCKEVENT_reset_cnts], 0200,
+	if (IS_ERR(debugfs_create_file(lockevent_names[LOCKEVENT_reset_cnts], 0200,
 				 d_counts, (void *)(long)LOCKEVENT_reset_cnts,
-				 &fops_lockevent))
+				 &fops_lockevent)))
 		goto fail_undo;
 
 	return 0;