regmap: change regmap_init_mem() to take ofnode instead udevice

Currently, regmap_init_mem() takes a udevice. This requires the node
has already been associated with a device. It prevents syscon/regmap
from behaving like those in Linux.

Change the first argumenet to take a device node.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/include/regmap.h b/include/regmap.h
index d827a0b..e96c79d 100644
--- a/include/regmap.h
+++ b/include/regmap.h
@@ -47,10 +47,10 @@
  *
  * Use regmap_uninit() to free it.
  *
- * @dev:	Device that uses this map
+ * @node:	Device node that uses this map
  * @mapp:	Returns allocated map
  */
-int regmap_init_mem(struct udevice *dev, struct regmap **mapp);
+int regmap_init_mem(ofnode node, struct regmap **mapp);
 
 /**
  * regmap_init_mem_platdata() - Set up a new memory register map for of-platdata