ARM: dts: imx7s-warp: Add User Button support

Add User Button at GPIO7_1.

Tested by evtest.
Signed-off-by: Vanessa Maegima <vanessa.maegima@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx7s-warp.dts

@@ -54,6 +54,19 @@ memory {
 		reg = <0x80000000 0x20000000>;
 	};
 
+	gpio-keys {
+		compatible = "gpio-keys";
+		pinctrl-0 = <&pinctrl_gpio>;
+		autorepeat;
+
+		back {
+			label = "Back";
+			gpios = <&gpio7 1 GPIO_ACTIVE_HIGH>;
+			linux,code = <KEY_BACK>;
+			wakeup-source;
+		};
+	};
+
 	reg_brcm: regulator-brcm {
 		compatible = "regulator-fixed";
 		enable-active-high;
@@ -280,6 +293,12 @@ MX7D_PAD_SD2_WP__GPIO5_IO10	0x14 /* WL_REG_ON */
 		>;
 	};
 
+	pinctrl_gpio: gpiogrp {
+		fsl,pins = <
+			MX7D_PAD_ENET1_RGMII_RD1__GPIO7_IO1	0x14
+		>;
+	};
+
 	pinctrl_i2c1: i2c1grp {
 		fsl,pins = <
 			MX7D_PAD_I2C1_SDA__I2C1_SDA		0x4000007f