arm64: dts: librem5-devkit: allow modem to wake the system from suspend

Connect the WoWWAN signal to a gpio key to wake up the system from suspend.
Signed-off-by: Angus Ainslie (Purism) <angus@akkea.ca>
Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts

@@ -55,6 +55,15 @@ hp-det {
 			wakeup-source;
 			linux,code = <KEY_HP>;
 		};
+
+		wwan-wake {
+			label = "WWAN_WAKE";
+			gpios = <&gpio3 8 GPIO_ACTIVE_LOW>;
+			interrupt-parent = <&gpio3>;
+			interrupts = <8 GPIO_ACTIVE_LOW>;
+			wakeup-source;
+			linux,code = <KEY_PHONE>;
+		};
 	};
 
 	leds {
@@ -576,6 +585,7 @@ pinctrl_gpio_keys: gpiokeygrp {
 			MX8MQ_IOMUXC_SAI2_RXFS_GPIO4_IO21	0x16
 			MX8MQ_IOMUXC_SAI2_RXC_GPIO4_IO22	0x16
 			MX8MQ_IOMUXC_SAI5_RXC_GPIO3_IO20	0x180  /* HP_DET */
+			MX8MQ_IOMUXC_NAND_DATA02_GPIO3_IO8	0x80   /* nWoWWAN */
 		>;
 	};