ARM: dts: exynos: Align L2 cache-controller nodename with dtschema

Fix dtschema warning message by changing nodename to 'cache-controller':

    DT_SCHEMA_FILES=Documentation/devicetree/bindings/arm/l2c2x0.yaml
    arch/arm/boot/dts/exynos4210-i9100.dt.yaml: l2-cache-controller@10502000:
	$nodename:0: 'l2-cache-controller@10502000' does not match '
	^(cache-controller|cpu)(@[0-9a-f,]+)*$'
Signed-off-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

arch/arm/boot/dts/exynos4210.dtsi

@@ -97,7 +97,7 @@ pd_lcd1: power-domain@10023ca0 {
 			label = "LCD1";
 		};
 
-		l2c: l2-cache-controller@10502000 {
+		l2c: cache-controller@10502000 {
 			compatible = "arm,pl310-cache";
 			reg = <0x10502000 0x1000>;
 			cache-unified;

arch/arm/boot/dts/exynos4412.dtsi

@@ -213,7 +213,7 @@ pd_isp: power-domain@10023ca0 {
 			label = "ISP";
 		};
 
-		l2c: l2-cache-controller@10502000 {
+		l2c: cache-controller@10502000 {
 			compatible = "arm,pl310-cache";
 			reg = <0x10502000 0x1000>;
 			cache-unified;