ARM: kirkwood: Add support second I2C bus and RTC on OpenBlocks A6

OpenBlocks A6 uses second I2C with RTC of s35390a.
This supports them.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

arch/arm/boot/dts/kirkwood-openblocks_a6.dts

 /dts-v1/;
 
 /include/ "kirkwood.dtsi"
+/include/ "kirkwood-6282.dtsi"
 
 / {
 	model = "Plat'Home OpenBlocksA6";
@@ -35,5 +36,14 @@ sata@80000 {
 			nr-ports = <1>;
 			status = "okay";
 		};
+
+		i2c@11100 {
+			status = "okay";
+
+			s35390a: s35390a@30 {
+				compatible = "s35390a";
+				reg = <0x30>;
+			};
+		};
 	};
 };