Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/powerpc/kernel/firmware.c b/arch/powerpc/kernel/firmware.c
index 2eae447..cc4a5e3 100644
--- a/arch/powerpc/kernel/firmware.c
+++ b/arch/powerpc/kernel/firmware.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *  Extracted from cputable.c
  *
@@ -6,11 +7,6 @@
  *  Modifications for ppc64:
  *      Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
  *  Copyright (C) 2005 Stephen Rothwell, IBM Corporation
- *
- *  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.
  */
 
 #include <linux/export.h>