arm64: dts: freescale: imx8: Fix the system-controller node name

The proper name is 'system-controller', not 'scu'.
Signed-off-by: Viorel Suman <viorel.suman@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8qm.dtsi

@@ -181,7 +181,7 @@ timer {
 			     <GIC_PPI 10 IRQ_TYPE_LEVEL_LOW>; /* Hypervisor */
 	};
 
-	scu {
+	system-controller {
 		compatible = "fsl,imx-scu";
 		mbox-names = "tx0",
 			     "rx0",

arch/arm64/boot/dts/freescale/imx8qxp.dtsi

@@ -201,7 +201,7 @@ psci {
 		method = "smc";
 	};
 
-	scu {
+	system-controller {
 		compatible = "fsl,imx-scu";
 		mbox-names = "tx0",
 			     "rx0",