ARM: dts: fix usb pin control for imx-rex dts

This fixes a duplicated pin control causing this error:

imx6q-pinctrl 20e0000.iomuxc: pin MX6Q_PAD_GPIO_1 already
requested by regulators:regulator@2; cannot claim for 2184000.usb
imx6q-pinctrl 20e0000.iomuxc: pin-137 (2184000.usb) status -22
imx6q-pinctrl 20e0000.iomuxc: could not request pin 137
(MX6Q_PAD_GPIO_1) from group usbotggrp  on device 20e0000.iomuxc
imx_usb 2184000.usb: Error applying setting, reverse things
back
imx6q-pinctrl 20e0000.iomuxc: pin MX6Q_PAD_EIM_D31 already
requested by regulators:regulator@1; cannot claim for 2184200.usb
imx6q-pinctrl 20e0000.iomuxc: pin-52 (2184200.usb) status -22
imx6q-pinctrl 20e0000.iomuxc: could not request pin 52 (MX6Q_PAD_EIM_D31)
from group usbh1grp  on device 20e0000.iomuxc
imx_usb 2184200.usb: Error applying setting, reverse things
back
Signed-off-by: Felipe F. Tonello <eu@felipetonello.com>
Fixes: e2047e33 ("ARM: dts: add initial Rex Pro board support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

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

@@ -35,7 +35,6 @@ reg_usbh1_vbus: regulator@1 {
 			compatible = "regulator-fixed";
 			reg = <1>;
 			pinctrl-names = "default";
-			pinctrl-0 = <&pinctrl_usbh1>;
 			regulator-name = "usbh1_vbus";
 			regulator-min-microvolt = <5000000>;
 			regulator-max-microvolt = <5000000>;
@@ -47,7 +46,6 @@ reg_usb_otg_vbus: regulator@2 {
 			compatible = "regulator-fixed";
 			reg = <2>;
 			pinctrl-names = "default";
-			pinctrl-0 = <&pinctrl_usbotg>;
 			regulator-name = "usb_otg_vbus";
 			regulator-min-microvolt = <5000000>;
 			regulator-max-microvolt = <5000000>;