Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/sh/boards/mach-microdev/io.c b/arch/sh/boards/mach-microdev/io.c
index acdafb0..a76c127 100644
--- a/arch/sh/boards/mach-microdev/io.c
+++ b/arch/sh/boards/mach-microdev/io.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/arch/sh/boards/superh/microdev/io.c
  *
@@ -6,9 +7,6 @@
  * Copyright (C) 2004 Paul Mundt
  *
  * SuperH SH4-202 MicroDev board support.
- *
- * May be copied or modified under the terms of the GNU General Public
- * License.  See linux/COPYING for more information.
  */
 
 #include <linux/init.h>