Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm/lib/strchr.S b/arch/arm/lib/strchr.S
index 013d64c..09e2cc8 100644
--- a/arch/arm/lib/strchr.S
+++ b/arch/arm/lib/strchr.S
@@ -1,12 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  *  linux/arch/arm/lib/strchr.S
  *
  *  Copyright (C) 1995-2000 Russell King
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
  *  ASM optimised string functions
  */
 #include <linux/linkage.h>