ARM: dts: r9a06g032: Add missing '#power-domain-cells'

Without '#power-domain-cells' property, power-domains cannot
be used. This property is noted required in the device-tree
binding.

Add '#power-domain-cells' as needed.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Link: https://lore.kernel.org/r/20220422120850.769480-6-herve.codina@bootlin.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arch/arm/boot/dts/r9a06g032.dtsi

@@ -87,6 +87,7 @@
 			reg = <0x4000c000 0x1000>;
 			status = "okay";
 			#clock-cells = <1>;
+			#power-domain-cells = <0>;
 
 			clocks = <&ext_mclk>, <&ext_rtc_clk>,
 					<&ext_jtag_clk>, <&ext_rgmii_ref>;