arm: dts: en7523: add pinctrl/gpio support, drop legacy gpio support

This patch adds pinctrl/gpio dts nodes for airoha pinctrl driver.
It also removes legacy gpio nodes.

It should not be very dangerous, because:
 * No official EN7523 gpio support present in U-Boot
 * The same driver is planned for upstream linux/openwrt

Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
Reviewed-by: David Lechner <dlechner@baylibre.com>

arch/arm/dts/en7523-u-boot.dtsi

@@ -2,6 +2,9 @@
 
 #include <dt-bindings/reset/airoha,en7523-reset.h>
 
+/delete-node/ &gpio0;
+/delete-node/ &gpio1;
+
 / {
 	reserved-memory {
 		#address-cells = <1>;
@@ -22,6 +25,26 @@
 		#reset-cells = <1>;
 	};
 
+	system-controller@1fbf0200 {
+		compatible = "syscon", "simple-mfd";
+		reg = <0x1fbf0200 0xc0>;
+
+		en7523_pinctrl: pinctrl {
+			compatible = "airoha,en7523-pinctrl";
+
+			interrupt-parent = <&gic>;
+			interrupts = <GIC_SPI 26 IRQ_TYPE_LEVEL_HIGH>;
+
+			gpio-controller;
+			#gpio-cells = <2>;
+
+			interrupt-controller;
+			#interrupt-cells = <2>;
+
+			gpio-ranges = <&en7523_pinctrl 0 12 30>;
+		};
+	};
+
 	eth: ethernet@1fb50000 {
 		compatible = "airoha,en7523-eth";
 		reg = <0x1fb50000 0x2600>,