Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/usb/serial/omninet.c b/drivers/usb/serial/omninet.c
index e51c946..5b6e982 100644
--- a/drivers/usb/serial/omninet.c
+++ b/drivers/usb/serial/omninet.c
@@ -4,7 +4,7 @@
  *
  * Copyright (C) 2013,2017 Johan Hovold <johan@kernel.org>
  *
- * See Documentation/usb/usb-serial.txt for more information on using this
+ * See Documentation/usb/usb-serial.rst for more information on using this
  * driver
  *
  * Please report both successes and troubles to the author at omninet@kroah.com