Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/ia64/include/asm/acpi-ext.h b/arch/ia64/include/asm/acpi-ext.h
index 7f8362b..eaa5758 100644
--- a/arch/ia64/include/asm/acpi-ext.h
+++ b/arch/ia64/include/asm/acpi-ext.h
@@ -1,12 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * (c) Copyright 2003, 2006 Hewlett-Packard Development Company, L.P.
  *	Alex Williamson <alex.williamson@hp.com>
  *	Bjorn Helgaas <bjorn.helgaas@hp.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.
- *
  * Vendor specific extensions to ACPI.
  */