virtio_blk: add error handling support for add_disk()

We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20210818144542.19305-11-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

drivers/block/virtio_blk.c

@@ -875,9 +875,14 @@ static int virtblk_probe(struct virtio_device *vdev)
 	virtblk_update_capacity(vblk, false);
 	virtio_device_ready(vdev);
 
-	device_add_disk(&vdev->dev, vblk->disk, virtblk_attr_groups);
+	err = device_add_disk(&vdev->dev, vblk->disk, virtblk_attr_groups);
+	if (err)
+		goto out_cleanup_disk;
+
 	return 0;
 
+out_cleanup_disk:
+	blk_cleanup_disk(vblk->disk);
 out_free_tags:
 	blk_mq_free_tag_set(&vblk->tag_set);
 out_free_vq: