boards: nxp: imx91_evk: add GPIO support

Add gpio in board yaml file, gpio2 is enabled by default.
Add btn and led nodes to ensure the button and blinky samples can work.
Add board overlay file for driver test case: gpio_basic_api.

Signed-off-by: Zongchun Yu <zongchun.yu@nxp.com>

Author: ZongchunYu

boards/nxp/imx91_evk/imx91_evk_mimx9131.dts

@@ -8,6 +8,7 @@
 
 #include <nxp/nxp_mimx91.dtsi>
 #include "imx91_evk-pinctrl.dtsi"
+#include <zephyr/dt-bindings/input/input-event-codes.h>
 
 / {
 	model = "NXP i.MX91 A55";
@@ -24,6 +25,44 @@
 		reg = <0x80000000 DT_SIZE_M(1)>;
 	};
 
+	aliases {
+		led0 = &led_r;
+		led1 = &led_g;
+		sw0 = &btn_1;
+	};
+
+	leds {
+		compatible = "gpio-leds";
+		led_r: led_r {
+			label = "LED_R";
+			gpios = <&gpio2 13 GPIO_ACTIVE_HIGH>;
+		};
+		led_g: led_g {
+			label = "LED_G";
+			gpios = <&gpio2 4 GPIO_ACTIVE_HIGH>;
+		};
+		led_b: led_b {
+			label = "LED_B";
+			gpios = <&gpio2 12 GPIO_ACTIVE_HIGH>;
+		};
+	};
+
+	keys {
+		compatible = "gpio-keys";
+
+		btn_1: btn_1{
+			label = "BTN1";
+			gpios = <&gpio2 23 GPIO_ACTIVE_LOW>;
+			zephyr,code = <INPUT_KEY_0>;
+		};
+
+		btn_2: btn_2{
+			label = "BTN2";
+			gpios = <&gpio2 24 GPIO_ACTIVE_LOW>;
+			zephyr,code = <INPUT_KEY_1>;
+		};
+	};
+
 };
 
 &lpuart1 {
@@ -32,3 +71,7 @@
 	pinctrl-0 = <&uart1_default>;
 	pinctrl-names = "default";
 };
+
+&gpio2{
+	status = "okay";
+};

boards/nxp/imx91_evk/imx91_evk_mimx9131.yaml

@@ -13,5 +13,6 @@ toolchain:
   - cross-compile
 ram: 1024
 supported:
+  - gpio
   - uart
 vendor: nxp

tests/drivers/gpio/gpio_basic_api/boards/imx91_evk_mimx9131.overlay

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2025 NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/{
+	resources {
+		compatible = "test-gpio-basic-api";
+		/*
+		 * Use connector J1001 Pin 8 which connect to EXP_GPIO_IO14 as input
+		 * GPIO, and connector J1001 Pin 33 which connect to EXP_GPIO_IO13 as
+		 * output GPIO, connect these two pins with a Dupont Line.
+		 */
+		out-gpios = <&gpio2 13 0>;
+		in-gpios = <&gpio2 14 0>;
+	};
+};