Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/mfd/syscon.h b/include/linux/mfd/syscon.h
index 40a76b9..112dc66 100644
--- a/include/linux/mfd/syscon.h
+++ b/include/linux/mfd/syscon.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
  * System Control Driver
  *
@@ -5,11 +6,6 @@
  * Copyright (C) 2012 Linaro Ltd.
  *
  * Author: Dong Aisheng <dong.aisheng@linaro.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.
  */
 
 #ifndef __LINUX_MFD_SYSCON_H__
@@ -21,13 +17,18 @@
 struct device_node;
 
 #ifdef CONFIG_MFD_SYSCON
+extern struct regmap *device_node_to_regmap(struct device_node *np);
 extern struct regmap *syscon_node_to_regmap(struct device_node *np);
 extern struct regmap *syscon_regmap_lookup_by_compatible(const char *s);
-extern struct regmap *syscon_regmap_lookup_by_pdevname(const char *s);
 extern struct regmap *syscon_regmap_lookup_by_phandle(
 					struct device_node *np,
 					const char *property);
 #else
+static inline struct regmap *device_node_to_regmap(struct device_node *np)
+{
+	return ERR_PTR(-ENOTSUPP);
+}
+
 static inline struct regmap *syscon_node_to_regmap(struct device_node *np)
 {
 	return ERR_PTR(-ENOTSUPP);
@@ -38,11 +39,6 @@
 	return ERR_PTR(-ENOTSUPP);
 }
 
-static inline struct regmap *syscon_regmap_lookup_by_pdevname(const char *s)
-{
-	return ERR_PTR(-ENOTSUPP);
-}
-
 static inline struct regmap *syscon_regmap_lookup_by_phandle(
 					struct device_node *np,
 					const char *property)