ARM: dts: iwg20d-q7: Add RTC support

Define the iWave RainboW-G20D-Qseven board dependent part of the
RTC device node.
Signed-off-by: NBiju Das <biju.das@bp.renesas.com>
Signed-off-by: NChris Paterson <chris.paterson2@renesas.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7743-iwg20d-q7.dts

@@ -50,6 +50,11 @@
 };
 
 &pfc {
+	i2c2_pins: i2c2 {
+		groups = "i2c2";
+		function = "i2c2";
+	};
+
 	scif0_pins: scif0 {
 		groups = "scif0_data_d";
 		function = "scif0";
@@ -107,3 +112,16 @@
 	sd-uhs-sdr50;
 	status = "okay";
 };
+
+&i2c2 {
+	pinctrl-0 = <&i2c2_pins>;
+	pinctrl-names = "default";
+
+	status = "okay";
+	clock-frequency = <400000>;
+
+	rtc@68 {
+		compatible = "ti,bq32000";
+		reg = <0x68>;
+	};
+};