ARM: dts: imx7d-zii-rpu2: Remove unneeded snvs_pwrkey node

Since commit 4664179f ("ARM: dts: imx7s: Enable SNVS power key
according to board design") snvs_pwrkey is disabled by default, so there
is no need for disabling it explicitly in the board dts anymore.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Chris Healy <cphealy@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx7d-zii-rpu2.dts

@@ -669,10 +669,6 @@ &snvs_rtc {
 	status = "disabled";
 };
 
-&snvs_pwrkey {
-	status = "disabled";
-};
-
 &iomuxc {
 	pinctrl_ecspi1: ecspi1grp {
 		fsl,pins = <