Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c
index 1f32caa..00ec4f2 100644
--- a/drivers/acpi/acpi_platform.c
+++ b/drivers/acpi/acpi_platform.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * ACPI support for platform bus type.
  *
@@ -5,10 +6,6 @@
  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
  *          Mathias Nyman <mathias.nyman@linux.intel.com>
  *          Rafael J. Wysocki <rafael.j.wysocki@intel.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/acpi.h>