md/raid0: Fix an error message in raid0_make_request()

The first argument to WARN() is supposed to be a condition.  The
original code will just print the mdname() instead of the full warning
message.

Fixes: c84a137 ("md/raid0: avoid RAID0 data corruption due to layout confusion.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Song Liu <songliubraving@fb.com>

drivers/md/raid0.c

@@ -615,7 +615,7 @@ static bool raid0_make_request(struct mddev *mddev, struct bio *bio)
 		tmp_dev = map_sector(mddev, zone, sector, &sector);
 		break;
 	default:
-		WARN("md/raid0:%s: Invalid layout\n", mdname(mddev));
+		WARN(1, "md/raid0:%s: Invalid layout\n", mdname(mddev));
 		bio_io_error(bio);
 		return true;
 	}