drbd: don't set ->bd_contains

The ->bd_contains field is set by __blkdev_get and drivers have no
business manipulating it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/drbd/drbd_main.c

@@ -2766,8 +2766,6 @@ enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsig
 	disk->private_data = device;
 
 	device->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
-	/* we have no partitions. we contain only ourselves. */
-	device->this_bdev->bd_contains = device->this_bdev;
 
 	blk_queue_write_cache(q, true, true);
 	/* Setting the max_hw_sectors to an odd value of 8kibyte here