Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/powerpc/kernel/setup.h b/arch/powerpc/kernel/setup.h
index c6a592b..c82577c 100644
--- a/arch/powerpc/kernel/setup.h
+++ b/arch/powerpc/kernel/setup.h
@@ -1,12 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
  * Prototypes for functions that are shared between setup_(32|64|common).c
  *
  * Copyright 2016 Michael Ellerman, IBM Corporation.
- *
- * 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.
  */
 
 #ifndef __ARCH_POWERPC_KERNEL_SETUP_H