Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/rtc/rtc-m41t94.c b/drivers/rtc/rtc-m41t94.c
index bab82b4..6803b02 100644
--- a/drivers/rtc/rtc-m41t94.c
+++ b/drivers/rtc/rtc-m41t94.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Driver for ST M41T94 SPI RTC
  *
  * Copyright (C) 2008 Kim B. Heino
- *
- * 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/module.h>