arm64: dts: imx8mm: Reinstate GPIO watchdog always-running property on eDM SBC

The GPIO watchdog property name is 'always-running', not 'always-enabled'.
Use the correct property name and reinstate it into the DT.

Fixes: eff6b33c ("arm64: dts: imx8mm: Remove watchdog always-enabled property from eDM SBC")
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mm-data-modul-edm-sbc.dts

@@ -88,6 +88,7 @@ watchdog {
 		pinctrl-names = "default";
 		pinctrl-0 = <&pinctrl_watchdog_gpio>;
 		compatible = "linux,wdt-gpio";
+		always-running;
 		gpios = <&gpio1 8 GPIO_ACTIVE_HIGH>;
 		hw_algo = "level";
 		/* Reset triggers in 2..3 seconds */