ARM: dts: r8a7794: Fix W=1 dtc warnings

Warning (unit_address_vs_reg): Node /cache-controller@1 has a unit name, but no reg property

Move the cache-controller node under the cpus node, and make its unit
name and reg property match the MPIDR value.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7794.dtsi

@@ -55,13 +55,14 @@ cpu1: cpu@1 {
 			power-domains = <&sysc R8A7794_PD_CA7_CPU1>;
 			next-level-cache = <&L2_CA7>;
 		};
-	};
 
-	L2_CA7: cache-controller@1 {
-		compatible = "cache";
-		power-domains = <&sysc R8A7794_PD_CA7_SCU>;
-		cache-unified;
-		cache-level = <2>;
+		L2_CA7: cache-controller@0 {
+			compatible = "cache";
+			reg = <0>;
+			power-domains = <&sysc R8A7794_PD_CA7_SCU>;
+			cache-unified;
+			cache-level = <2>;
+		};
 	};
 
 	gic: interrupt-controller@f1001000 {