Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h
index b04c5ce..94e3fd5 100644
--- a/arch/powerpc/include/asm/prom.h
+++ b/arch/powerpc/include/asm/prom.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 #ifndef _POWERPC_PROM_H
 #define _POWERPC_PROM_H
 #ifdef __KERNEL__
@@ -9,11 +10,6 @@
  * Copyright (C) 1996-2005 Paul Mackerras.
  *
  * Updates for PPC64 by Peter Bergner & David Engebretsen, IBM Corp.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
  */
 #include <linux/types.h>
 #include <asm/irq.h>