ARM: dtsi: imx6qdl-sabresd: add a fixed regulator for WM8962

On Sabre SD, system controls WM8962 power by pulling up/down GPIO_4_10,
so add a regulator controled by GPIO_4_10 for WM8962.
Signed-off-by: Nicolin Chen <b42378@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

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

@@ -26,6 +26,13 @@ reg_usb_otg_vbus: usb_otg_vbus {
 			gpio = <&gpio3 22 0>;
 			enable-active-high;
 		};
+
+		reg_audio: wm8962_supply {
+			compatible = "regulator-fixed";
+			regulator-name = "wm8962-supply";
+			gpio = <&gpio4 10 0>;
+			enable-active-high;
+		};
 	};
 
 	gpio-keys {