Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/powerpc/lib/quad.S b/arch/powerpc/lib/quad.S
index c4d12fa..da71760 100644
--- a/arch/powerpc/lib/quad.S
+++ b/arch/powerpc/lib/quad.S
@@ -1,13 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
  * Quadword loads and stores
  * for use in instruction emulation.
  *
  * Copyright 2017 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
- *
- *  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 <asm/processor.h>