drbd: Remove obsolete check

Smatch complained about it this redundanct check.

The check was introduced in 2006-09-13. On 2007-07-24 the body of the
function was enclosed by get_ldev()/put_ldev() reference counting.
Since then the check is useless and miss leading.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

drivers/block/drbd/drbd_main.c

@@ -840,7 +840,7 @@ int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
 	}
 	spin_lock_irq(&mdev->ldev->md.uuid_lock);
 	for (i = UI_CURRENT; i < UI_SIZE; i++)
-		p->uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
+		p->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
 	spin_unlock_irq(&mdev->ldev->md.uuid_lock);
 
 	mdev->comm_bm_set = drbd_bm_total_weight(mdev);