Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/openrisc/kernel/prom.c b/arch/openrisc/kernel/prom.c
index 6a44340..19e6008 100644
--- a/arch/openrisc/kernel/prom.c
+++ b/arch/openrisc/kernel/prom.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * OpenRISC prom.c
  *
@@ -8,14 +9,8 @@
  * Modifications for the OpenRISC architecture:
  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
  *
- *      This program is free software; you can redistribute it and/or
- *      modify it under the terms of the GNU General Public License
- *      as published by the Free Software Foundation; either version
- *      2 of the License, or (at your option) any later version.
- *
  * Architecture specific procedures for creating, accessing and
  * interpreting the device tree.
- *
  */
 
 #include <linux/init.h>