arm64: dts: realtek: add missing cache properties

As all level 2 and level 3 caches are unified, add required
cache-unified and cache-level properties to fix warnings like:

  rtd1293-ds418j.dtb: l2-cache: 'cache-level' is a required property
  rtd1293-ds418j.dtb: l2-cache: 'cache-unified' is a required property

Link: https://lore.kernel.org/r/20230421223151.115243-1-krzysztof.kozlowski@linaro.orgSigned-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

arch/arm64/boot/dts/realtek/rtd1293.dtsi

@@ -30,6 +30,8 @@ cpu1: cpu@1 {
 
 		l2: l2-cache {
 			compatible = "cache";
+			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm64/boot/dts/realtek/rtd1295.dtsi

@@ -44,6 +44,8 @@ cpu3: cpu@3 {
 
 		l2: l2-cache {
 			compatible = "cache";
+			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm64/boot/dts/realtek/rtd1296.dtsi

@@ -44,6 +44,8 @@ cpu3: cpu@3 {
 
 		l2: l2-cache {
 			compatible = "cache";
+			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm64/boot/dts/realtek/rtd1395.dtsi

@@ -44,6 +44,8 @@ cpu3: cpu@3 {
 
 		l2: l2-cache {
 			compatible = "cache";
+			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm64/boot/dts/realtek/rtd16xx.dtsi

@@ -88,11 +88,15 @@ cpu5: cpu@500 {
 		l2: l2-cache {
 			compatible = "cache";
 			next-level-cache = <&l3>;
+			cache-level = <2>;
+			cache-unified;
 
 		};
 
 		l3: l3-cache {
 			compatible = "cache";
+			cache-level = <3>;
+			cache-unified;
 		};
 	};