writeback: add name to backing_dev_info

This enables us to track who does what and print info. Its main use
is catching dirty inodes on the default_backing_dev_info, so we can
fix that up.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

drivers/block/aoe/aoeblk.c

@@ -268,6 +268,7 @@ aoeblk_gdalloc(void *vp)
 	if (!d->blkq)
 		goto err_mempool;
 	blk_queue_make_request(d->blkq, aoeblk_make_request);
+	d->blkq->backing_dev_info.name = "aoe";
 	if (bdi_init(&d->blkq->backing_dev_info))
 		goto err_blkq;
 	spin_lock_irqsave(&d->lock, flags);