Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
index 9132c5c..c066fec 100644
--- a/include/linux/pageblock-flags.h
+++ b/include/linux/pageblock-flags.h
@@ -1,20 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Macros for manipulating and testing flags related to a
  * pageblock_nr_pages number of pages.
  *
- * 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 version 2 of the License
- *
- * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
  * Copyright (C) IBM Corporation, 2006
  *
  * Original author, Mel Gorman
@@ -25,10 +13,11 @@
 
 #include <linux/types.h>
 
+#define PB_migratetype_bits 3
 /* Bit indices that affect a whole block of pages */
 enum pageblock_bits {
 	PB_migrate,
-	PB_migrate_end = PB_migrate + 3 - 1,
+	PB_migrate_end = PB_migrate + PB_migratetype_bits - 1,
 			/* 3 bits required for migrate types */
 	PB_migrate_skip,/* If set the block is skipped by compaction */