arm64: dts: ti: add missing cache properties

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

  k3-am6528-iot2050-basic-pg2.dtb: l3-cache0: 'cache-unified' is a required property
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Nishanth Menon <nm@ti.com>
Link: https://lore.kernel.org/r/20230421223143.115099-1-krzysztof.kozlowski@linaro.orgSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>

arch/arm64/boot/dts/ti/k3-am654.dtsi

@@ -113,6 +113,7 @@ L2_1: l2-cache1 {
 	msmc_l3: l3-cache0 {
 		compatible = "cache";
 		cache-level = <3>;
+		cache-unified;
 	};
 
 	thermal_zones: thermal-zones {

arch/arm64/boot/dts/ti/k3-j7200.dtsi

@@ -95,6 +95,7 @@ L2_0: l2-cache0 {
 	msmc_l3: l3-cache0 {
 		compatible = "cache";
 		cache-level = <3>;
+		cache-unified;
 	};
 
 	firmware {

arch/arm64/boot/dts/ti/k3-j721e.dtsi

@@ -97,6 +97,7 @@ L2_0: l2-cache0 {
 	msmc_l3: l3-cache0 {
 		compatible = "cache";
 		cache-level = <3>;
+		cache-unified;
 	};
 
 	firmware {

arch/arm64/boot/dts/ti/k3-j721s2.dtsi

@@ -81,6 +81,7 @@ L2_0: l2-cache0 {
 	msmc_l3: l3-cache0 {
 		compatible = "cache";
 		cache-level = <3>;
+		cache-unified;
 	};
 
 	firmware {