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/drivers/ram/rockchip/sdram_rk3399.c b/drivers/ram/rockchip/sdram_rk3399.c
index d16ff0d..49ebd88 100644
--- a/drivers/ram/rockchip/sdram_rk3399.c
+++ b/drivers/ram/rockchip/sdram_rk3399.c
@@ -1098,7 +1098,7 @@
 		       __func__, ret);
 		return ret;
 	}
-	ret = regmap_init_mem(dev, &plat->map);
+	ret = regmap_init_mem(dev_ofnode(dev), &plat->map);
 	if (ret)
 		printf("%s: regmap failed %d\n", __func__, ret);