ARM: dts: axp22x/axp809: Add GPIO controller nodes

These PMICs all contain a GPIO controller. Now that the binding for this
variant is documented, wire up the controller in the device tree.

Signed-off-by: Samuel Holland <[e-mail]>
Acked-by: Jernej Skrabec <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jernej Skrabec <[e-mail]>

arch/arm/boot/dts/axp22x.dtsi

···
 		status = "disabled";
 	};
 
+	axp_gpio: gpio {
+		compatible = "x-powers,axp221-gpio";
+		gpio-controller;
+		#gpio-cells = <2>;
+	};
+
 	regulators {
 		/* Default work frequency for buck regulators */
 		x-powers,dcdc-freq = <3000>;

arch/arm/boot/dts/axp809.dtsi

···
 	compatible = "x-powers,axp809";
 	interrupt-controller;
 	#interrupt-cells = <1>;
+
+	axp_gpio: gpio {
+		compatible = "x-powers,axp809-gpio",
+			     "x-powers,axp221-gpio";
+		gpio-controller;
+		#gpio-cells = <2>;
+	};
 };