arm: aspeed: dtsi: add reg for i2c

The i2c driver have global register that i2c bus use
ofnode_get_parent to get parent register address.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
diff --git a/arch/arm/dts/ast2600.dtsi b/arch/arm/dts/ast2600.dtsi
index 8d91eed..beabcf1 100644
--- a/arch/arm/dts/ast2600.dtsi
+++ b/arch/arm/dts/ast2600.dtsi
@@ -681,6 +681,7 @@
 
 			i2c: bus@1e78a000 {
 				compatible = "simple-bus";
+				reg = <0x1e78a000 0x1000>;
 				#address-cells = <1>;
 				#size-cells = <1>;
 				ranges = <0 0x1e78a000 0x1000>;