rt2x00: cancel all work on disconnect

Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/rt2x00dev.c

@@ -892,6 +892,12 @@ void rt2x00lib_remove_dev(struct rt2x00_dev *rt2x00dev)
 	 */
 	rt2x00lib_disable_radio(rt2x00dev);
 
+	/*
+	 * Stop all work.
+	 */
+	cancel_work_sync(&rt2x00dev->filter_work);
+	cancel_work_sync(&rt2x00dev->intf_work);
+
 	/*
 	 * Uninitialize device.
 	 */