ARM: at91: add pinctrl nodes to i2c-gpio on RM92000 DT

GPIO pins used by i2c-gpio must be set to multi drive
(open drain) to work properly.
Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/boot/dts/at91rm9200.dtsi

@@ -383,6 +383,12 @@ pinctrl_twi: twi-0 {
 							<0 25 0x1 0x2	/* PA25 periph A with multi drive */
 							 0 26 0x1 0x2>;	/* PA26 periph A with multi drive */
 					};
+
+					pinctrl_twi_gpio: twi_gpio-0 {
+						atmel,pins =
+							<0 25 0x0 0x2	/* PA25 GPIO with multi drive */
+							 0 26 0x0 0x2>;	/* PA26 GPIO with multi drive */
+					};
 				};
 
 				pioA: gpio@fffff400 {
@@ -520,6 +526,8 @@ &pioA 26 0 /* scl */
 		i2c-gpio,sda-open-drain;
 		i2c-gpio,scl-open-drain;
 		i2c-gpio,delay-us = <2>;	/* ~100 kHz */
+		pinctrl-names = "default";
+		pinctrl-0 = <&pinctrl_twi_gpio>;
 		#address-cells = <1>;
 		#size-cells = <0>;
 		status = "disabled";