[S390] cio: Use device_reprobe() instead of bus_rescan_devices().

In io_subchannel_register(), it is better to just reprobe the current
device if it hasn't a driver yet than to rescan the whole bus.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/device.c

@@ -687,8 +687,20 @@ io_subchannel_register(void *data)
 	cdev = data;
 	sch = to_subchannel(cdev->dev.parent);
 
+	/*
+	 * io_subchannel_register() will also be called after device
+	 * recognition has been done for a boxed device (which will already
+	 * be registered). We need to reprobe since we may now have sense id
+	 * information.
+	 */
 	if (klist_node_attached(&cdev->dev.knode_parent)) {
-		bus_rescan_devices(&ccw_bus_type);
+		if (!cdev->drv) {
+			ret = device_reprobe(&cdev->dev);
+			if (ret)
+				/* We can't do much here. */
+				dev_info(&cdev->dev, "device_reprobe() returned"
+					 " %d\n", ret);
+		}
 		goto out;
 	}
 	/* make it known to the system */