ARM: dts: broadcom: add missing cache properties

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

  bcm963148.dtb: l2-cache0: 'cache-unified' is a required property

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: William Zhang <william.zhang@broadcom.com>
Link: https://lore.kernel.org/r/20230423150943.118576-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

arch/arm/boot/dts/bcm47622.dtsi

@@ -52,6 +52,7 @@
 		L2_0: l2-cache0 {
 			compatible = "cache";
 			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm/boot/dts/bcm63148.dtsi

@@ -36,6 +36,7 @@
 		L2_0: l2-cache0 {
 			compatible = "cache";
 			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm/boot/dts/bcm63178.dtsi

@@ -44,6 +44,7 @@
 		L2_0: l2-cache0 {
 			compatible = "cache";
 			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm/boot/dts/bcm6756.dtsi

@@ -52,6 +52,7 @@
 		L2_0: l2-cache0 {
 			compatible = "cache";
 			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm/boot/dts/bcm6846.dtsi

@@ -36,6 +36,7 @@
 		L2_0: l2-cache0 {
 			compatible = "cache";
 			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm/boot/dts/bcm6855.dtsi

@@ -44,6 +44,7 @@
 		L2_0: l2-cache0 {
 			compatible = "cache";
 			cache-level = <2>;
+			cache-unified;
 		};
 	};
 

arch/arm/boot/dts/bcm6878.dtsi

@@ -36,6 +36,7 @@
 		L2_0: l2-cache0 {
 			compatible = "cache";
 			cache-level = <2>;
+			cache-unified;
 		};
 	};