arm64: dts: mt8173: Fix auxadc node

The devicetree node for mt8173-auxadc lacks the clock and
io-channel-cells property. This leads to a non-working driver.

	mt6577-auxadc 11001000.auxadc: failed to get auxadc clock
	mt6577-auxadc: probe of 11001000.auxadc failed with error -2

Fix these fields to get the device up and running.

Fixes: 748c7d4d ("ARM64: dts: mt8173: Add thermal/auxadc device
nodes")
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

arch/arm64/boot/dts/mediatek/mt8173.dtsi

@@ -450,6 +450,9 @@ gic: interrupt-controller@10220000 {
 		auxadc: auxadc@11001000 {
 			compatible = "mediatek,mt8173-auxadc";
 			reg = <0 0x11001000 0 0x1000>;
+			clocks = <&pericfg CLK_PERI_AUXADC>;
+			clock-names = "main";
+			#io-channel-cells = <1>;
 		};
 
 		uart0: serial@11002000 {