md: don't use locked_ioctl.

md has no need for the BKL - it does its own locking.
So md_ioctl doesn't need to be a locked_ioctl.
Signed-off-by: NeilBrown <neilb@suse.de>

drivers/md/md.c

@@ -5567,7 +5567,7 @@ static struct block_device_operations md_fops =
 	.owner		= THIS_MODULE,
 	.open		= md_open,
 	.release	= md_release,
-	.locked_ioctl	= md_ioctl,
+	.ioctl		= md_ioctl,
 	.getgeo		= md_getgeo,
 	.media_changed	= md_media_changed,
 	.revalidate_disk= md_revalidate,