[S390] cio: Use unbind/bind instead of unregister/register.

The common I/O layer may encounter a situation where the
device number of a ccw device has changed or a device
driver doesn't want to keep a formerly disconnected device
becoming operational again. Instead of using device_del()/
device_add() as now, we can just unbind the driver from the
device and rebind it to get the desired effect (rebinding)
with less overhead.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index 8df5eaa..95f2f35 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -194,7 +194,7 @@
 	    cdev->id.dev_type != cdev->private->senseid.dev_type ||
 	    cdev->id.dev_model != cdev->private->senseid.dev_model) {
 		PREPARE_WORK(&cdev->private->kick_work,
-			     ccw_device_do_unreg_rereg);
+			     ccw_device_do_unbind_bind);
 		queue_work(ccw_device_work, &cdev->private->kick_work);
 		return 0;
 	}
@@ -366,7 +366,7 @@
 	}
 	/* Driver doesn't want device back. */
 	ccw_device_set_notoper(cdev);
-	PREPARE_WORK(&cdev->private->kick_work, ccw_device_do_unreg_rereg);
+	PREPARE_WORK(&cdev->private->kick_work, ccw_device_do_unbind_bind);
 	queue_work(ccw_device_work, &cdev->private->kick_work);
 }