ARM: dts: at91: fix the GPIO polarity for onewire

The GPIO polarity for onewire must be GPIO_ACTIVE_HIGH.
On previous versions this used to work as it looks like the right flag values
are being passed since :
https://lists.denx.de/pipermail/u-boot/2020-April/407195.html

And that series broke the old functionality for onewire nodes.
Some boards had the correct value for the polarity, but it wasn't clear
so I replaced it with the right macro for the flag, instead of an empty value.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
diff --git a/arch/arm/dts/at91-sama5d2_xplained.dts b/arch/arm/dts/at91-sama5d2_xplained.dts
index 7f0d169..b733c4d 100644
--- a/arch/arm/dts/at91-sama5d2_xplained.dts
+++ b/arch/arm/dts/at91-sama5d2_xplained.dts
@@ -1,4 +1,5 @@
 /dts-v1/;
+#include <dt-bindings/gpio/gpio.h>
 #include "sama5d2.dtsi"
 #include "sama5d2-pinfunc.h"
 
@@ -12,7 +13,7 @@
 	};
 
 	onewire_tm: onewire {
-		gpios = <&pioA PIN_PB0 0>;
+		gpios = <&pioA PIN_PB0 GPIO_ACTIVE_HIGH>;
 		pinctrl-names = "default";
 		pinctrl-0 = <&pinctrl_onewire_tm_default>;
 		status = "okay";