Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm/common/firmware.c b/arch/arm/common/firmware.c
index 27ddccb..c1f8f58 100644
--- a/arch/arm/common/firmware.c
+++ b/arch/arm/common/firmware.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2012 Samsung Electronics.
  * Kyungmin Park <kyungmin.park@samsung.com>
  * Tomasz Figa <t.figa@samsung.com>
- *
- * 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.
  */
 
 #include <linux/kernel.h>