gdrom: change to use __blk_end_request()

This patch converts gdrom to use __blk_end_request() directly
so that end_{queued|dequeued}_request() can be removed.

gd.transfer is '1' in error cases and '0' in non-error cases,
so gdrom hasn't been propagating any error code to the block layer.
We can just convert error cases to '-EIO'.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

drivers/cdrom/gdrom.c

@@ -624,14 +624,14 @@ static void gdrom_readdisk_dma(struct work_struct *work)
 		ctrl_outb(1, GDROM_DMA_STATUS_REG);
 		wait_event_interruptible_timeout(request_queue,
 			gd.transfer == 0, GDROM_DEFAULT_TIMEOUT);
-		err = gd.transfer;
+		err = gd.transfer ? -EIO : 0;
 		gd.transfer = 0;
 		gd.pending = 0;
 		/* now seek to take the request spinlock
 		* before handling ending the request */
 		spin_lock(&gdrom_lock);
 		list_del_init(&req->queuelist);
-		end_dequeued_request(req, 1 - err);
+		__blk_end_request(req, err, blk_rq_bytes(req));
 	}
 	spin_unlock(&gdrom_lock);
 	kfree(read_command);