arm64: dts: meson-gxl-s905x-khadas-vim: fix gpio-keys-polled node

Fix DTC warnings:

arch/arm/dts/meson-gxl-s905x-khadas-vim.dtb: Warning (avoid_unnecessary_addr_size):
   /gpio-keys-polled: unnecessary #address-cells/#size-cells
      without "ranges" or child "reg" property

Fixes: e15d2774 ("ARM64: dts: meson-gxl: add support for the Khadas VIM board")
Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>

arch/arm64/boot/dts/amlogic/meson-gxl-s905x-khadas-vim.dts

@@ -33,11 +33,9 @@ aliases {
 
 	gpio-keys-polled {
 		compatible = "gpio-keys-polled";
-		#address-cells = <1>;
-		#size-cells = <0>;
 		poll-interval = <100>;
 
-		button@0 {
+		power-button {
 			label = "power";
 			linux,code = <KEY_POWER>;
 			gpios = <&gpio_ao GPIOAO_2 GPIO_ACTIVE_LOW>;