ARM: dts: imx6-sabreauto: add reset-gpios property for max7310_b

The reset pin to the port expander chip (MAX7310) is controlled by a gpio,
so define a reset-gpios property to control it. There are three MAX7310's
on the SabreAuto CPU card (max7310_[abc]), but all use the same pin for
their reset. Since all can't acquire the same pin, assign it to max7310_b,
that chip is needed by more functions (usb and adv7180).
Signed-off-by: NSteve Longerbeam <steve_longerbeam@mentor.com>
Reviewed-by: NFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: NShawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-sabreauto.dtsi

@@ -136,6 +136,9 @@
 				reg = <0x32>;
 				gpio-controller;
 				#gpio-cells = <2>;
+				pinctrl-names = "default";
+				pinctrl-0 = <&pinctrl_max7310>;
+				reset-gpios = <&gpio1 15 GPIO_ACTIVE_LOW>;
 			};
 
 			max7310_c: gpio@34 {
@@ -441,6 +444,12 @@
 			>;
 		};
 
+		pinctrl_max7310: max7310grp {
+			fsl,pins = <
+				MX6QDL_PAD_SD2_DAT0__GPIO1_IO15 0x1b0b0
+			>;
+		};
+
 		pinctrl_pwm3: pwm1grp {
 			fsl,pins = <
 				MX6QDL_PAD_SD4_DAT1__PWM3_OUT		0x1b0b1