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

Fix dtschema validator warnings like:
    l2-cache-controller@48242000: $nodename:0: 'l2-cache-controller@48242000'
        does not match '^(cache-controller|cpu)(@[0-9a-f,]+)*$'
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am4372.dtsi

@@ -153,7 +153,7 @@ local_timer: timer@48240600 {
 		clocks = <&mpu_periphclk>;
 	};
 
-	l2-cache-controller@48242000 {
+	cache-controller@48242000 {
 		compatible = "arm,pl310-cache";
 		reg = <0x48242000 0x1000>;
 		cache-unified;