[S390] dasd set offline kernel bug.

The request queue flush function of the dasd driver has to dequeue
the requests first and then call the end request function. Otherwise
a kernel bug in ll_rw_block.c might get triggered.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 4bf03fb..d8e9b95 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -1730,8 +1730,8 @@
 		req = elv_next_request(device->request_queue);
 		if (req == NULL)
 			break;
-		dasd_end_request(req, 0);
 		blkdev_dequeue_request(req);
+		dasd_end_request(req, 0);
 	}
 	spin_unlock_irq(&device->request_queue_lock);
 }