drbd: remove dead code in device_to_statistics

Ever since the switch to blk-mq, a lower device not used for VM
writeback will not be marked congested, so the check will never
trigger.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/drbd/drbd_nl.c

@@ -3370,7 +3370,6 @@ static void device_to_statistics(struct device_statistics *s,
 	if (get_ldev(device)) {
 		struct drbd_md *md = &device->ldev->md;
 		u64 *history_uuids = (u64 *)s->history_uuids;
-		struct request_queue *q;
 		int n;
 
 		spin_lock_irq(&md->uuid_lock);
@@ -3384,11 +3383,6 @@ static void device_to_statistics(struct device_statistics *s,
 		spin_unlock_irq(&md->uuid_lock);
 
 		s->dev_disk_flags = md->flags;
-		q = bdev_get_queue(device->ldev->backing_bdev);
-		s->dev_lower_blocked =
-			bdi_congested(q->backing_dev_info,
-				      (1 << WB_async_congested) |
-				      (1 << WB_sync_congested));
 		put_ldev(device);
 	}
 	s->dev_size = drbd_get_capacity(device->this_bdev);