arm64: dts: imx8qxp-mek: Enable scu key

Enable scu key for i.MX8QXP MEK board.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8qxp-mek.dts

@@ -234,3 +234,7 @@ IMX8QXP_USDHC1_VSELECT_CONN_USDHC1_VSELECT		0x00000021
 &adma_dsp {
 	status = "okay";
 };
+
+&scu_key {
+	status = "okay";
+};