arm64: dts: rockchip: Support poweroff on Edgeble Neural Compute Module

On Edgeble Neural Compute Module add system-power-controller
property to RK806 pmic so that these chips can power off the device.

Cc: Jagan Teki <jagan@edgeble.ai>
Signed-off-by: Anand Moon <anand@edgeble.ai>
Link: https://lore.kernel.org/r/20240502094246.4695-1-anand@edgeble.aiSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3588-edgeble-neu6a-common.dtsi

@@ -162,6 +162,8 @@ pmic@0 {
 		pinctrl-0 = <&pmic_pins>, <&rk806_dvs1_null>,
 			    <&rk806_dvs2_null>, <&rk806_dvs3_null>;
 
+		system-power-controller;
+
 		vcc1-supply = <&vcc5v0_sys>;
 		vcc2-supply = <&vcc5v0_sys>;
 		vcc3-supply = <&vcc5v0_sys>;