Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm/mach-mmp/common.c b/arch/arm/mach-mmp/common.c
index 685a099..6684abc 100644
--- a/arch/arm/mach-mmp/common.c
+++ b/arch/arm/mach-mmp/common.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/arch/arm/mach-mmp/common.c
  *
  *  Code common to PXA168 processor lines
- *
- * 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/init.h>