ARM: dts: imx6q-bx50v3: Add gpio power off support

bx50v3 boards can be powered off via GPIO, this patch specifies the GPIO to
be used with the gpio-poweroff driver.
Signed-off-by: NKen Lin <ken.lin@advantech.com.tw>
Signed-off-by: NAkshay Bhat <akshay.bhat@timesys.com>
Signed-off-by: NShawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6q-bx50v3.dtsi

@@ -52,6 +52,12 @@
 		};
 	};
 
+	gpio-poweroff {
+		compatible = "gpio-poweroff";
+		gpios = <&gpio4 11 GPIO_ACTIVE_LOW>;
+		status = "okay";
+	};
+
 	reg_wl18xx_vmmc: regulator-wl18xx {
 		compatible = "regulator-fixed";
 		regulator-name = "vwl1807";