dm raid: Remove empty if statement

In super_init_validation(), remove a body-less if statement testing only
variables to avoid a compilation warning when compiling with W=1.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-raid.c

@@ -2345,8 +2345,6 @@ static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
 
 	if (new_devs == rs->raid_disks || !rebuilds) {
 		/* Replace a broken device */
-		if (new_devs == 1 && !rs->delta_disks)
-			;
 		if (new_devs == rs->raid_disks) {
 			DMINFO("Superblocks created for new raid set");
 			set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);