ARM: dts: r8a73a4: Add clock for CA15 CPU0 core

Improve hardware description by adding a clocks property to the device
node corresponding to the primary CA15 CPU core, which is for now the
only one described.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a73a4.dtsi

@@ -27,6 +27,7 @@
 			device_type = "cpu";
 			compatible = "arm,cortex-a15";
 			reg = <0>;
+			clocks = <&cpg_clocks R8A73A4_CLK_Z>;
 			clock-frequency = <1500000000>;
 			power-domains = <&pd_a2sl>;
 			next-level-cache = <&L2_CA15>;