Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm/mach-highbank/system.c b/arch/arm/mach-highbank/system.c
index 2df5870..b749c4a 100644
--- a/arch/arm/mach-highbank/system.c
+++ b/arch/arm/mach-highbank/system.c
@@ -1,17 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright 2011 Calxeda, Inc.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include <linux/io.h>
 #include <asm/proc-fns.h>