ARM: dts: arm-realview: Align L2 cache-controller nodename with dtschema

Fix dtschema validator warnings like:
    l2-cache: $nodename:0: 'l2-cache' does not match '^(cache-controller|cpu)(@[0-9a-f,]+)*$'
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200626080534.3400-1-krzk@kernel.orgSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/arm-realview-eb-mp.dtsi

@@ -59,7 +59,7 @@ intc_second: interrupt-controller@10040000 {
 			interrupts = <0 10 IRQ_TYPE_LEVEL_HIGH>;
 		};
 
-		L2: l2-cache {
+		L2: cache-controller {
 			compatible = "arm,l220-cache";
 			reg = <0x1f002000 0x1000>;
 			interrupt-parent = <&intc>;

arch/arm/boot/dts/arm-realview-pb1176.dts

@@ -323,7 +323,7 @@ intc_dc1176: interrupt-controller@10120000 {
 			      <0x10120000 0x100>;
 		};
 
-		L2: l2-cache {
+		L2: cache-controller {
 			compatible = "arm,l220-cache";
 			reg = <0x10110000 0x1000>;
 			interrupt-parent = <&intc_dc1176>;

arch/arm/boot/dts/arm-realview-pb11mp.dts

@@ -92,7 +92,7 @@ intc_tc11mp: interrupt-controller@1f000100 {
 		      <0x1f000100 0x100>;
 	};
 
-	L2: l2-cache {
+	L2: cache-controller {
 		compatible = "arm,l220-cache";
 		reg = <0x1f002000 0x1000>;
 		interrupt-parent = <&intc_tc11mp>;

arch/arm/boot/dts/arm-realview-pbx-a9.dts

@@ -60,7 +60,7 @@ CPU1: cpu@1 {
 		};
 	};
 
-	L2: l2-cache {
+	L2: cache-controller {
 		compatible = "arm,pl310-cache";
 		reg = <0x1f002000 0x1000>;
 		cache-unified;