ARM64: dts: meson-gxbb-odroidc2: Enable SARADC node

Now that 3adbf34273 "iio: adc: add a driver for the SAR ADC found in
Amlogic Meson SoCs" has added support for the ADC, let's enable it
on Odroid C2.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>

arch/arm64/boot/dts/amlogic/meson-gxbb-odroidc2.dts

@@ -267,6 +267,11 @@
 	status = "okay";
 };
 
+&saradc {
+	status = "okay";
+	vref-supply = <&vcc1v8>;
+};
+
 /* SD */
 &sd_emmc_b {
 	status = "okay";