ARM: dts: rmobile: Add SoC and board U-Boot DT extras

Add U-Boot DT extras for each SoC and board. This marks the required
nodes with u-boot,dm-pre-reloc to start clock and PRR early on while
avoiding modification of the DTs imported from Linux.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/arch/arm/dts/r8a7792-blanche-u-boot.dts b/arch/arm/dts/r8a7792-blanche-u-boot.dts
new file mode 100644
index 0000000..7b94cd9
--- /dev/null
+++ b/arch/arm/dts/r8a7792-blanche-u-boot.dts
@@ -0,0 +1,10 @@
+/*
+ * Device Tree Source extras for U-Boot for the Blanche board
+ *
+ * Copyright (C) 2018 Marek Vasut <marek.vasut@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ */
+
+#include "r8a7792-blanche.dts"
+#include "r8a7792-u-boot.dtsi"