Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/acpi/acpi_extlog.c b/drivers/acpi/acpi_extlog.c
index 560fdae..8596a10 100644
--- a/drivers/acpi/acpi_extlog.c
+++ b/drivers/acpi/acpi_extlog.c
@@ -1,10 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Extended Error Log driver
  *
  * Copyright (C) 2013 Intel Corp.
  * Author: Chen, Gong <gong.chen@intel.com>
- *
- * This file is licensed under GPLv2.
  */
 
 #include <linux/module.h>