Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/mips/rb532/prom.c b/arch/mips/rb532/prom.c
index 6484e4a..26e957b 100644
--- a/arch/mips/rb532/prom.c
+++ b/arch/mips/rb532/prom.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *  RouterBoard 500 specific prom routines
  *
@@ -6,22 +7,6 @@
  *  Copyright (C) 2007, Gabor Juhos <juhosg@openwrt.org>
  *			Felix Fietkau <nbd@openwrt.org>
  *			Florian Fainelli <florian@openwrt.org>
- *
- *  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.
- *
- *  This program is distributed in the hope that 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, write to the
- *  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
- *  Boston, MA  02110-1301, USA.
- *
  */
 
 #include <linux/init.h>
@@ -29,7 +14,7 @@
 #include <linux/export.h>
 #include <linux/string.h>
 #include <linux/console.h>
-#include <linux/bootmem.h>
+#include <linux/memblock.h>
 #include <linux/ioport.h>
 #include <linux/blkdev.h>