ARM: dts: imx6dl: prtrvt, prtvt7, prti6q, prtwd2: fix USB related warnings

Fix USB-related warnings in prtrvt, prtvt7, prti6q and prtwd2 device trees
by disabling unused usbphynop1 and usbphynop2 USB PHYs and providing proper
configuration for the over-current detection. This fixes the following
warnings with the current kernel:
 usb_phy_generic usbphynop1: dummy supplies not allowed for exclusive requests
 usb_phy_generic usbphynop2: dummy supplies not allowed for exclusive requests
 imx_usb 2184200.usb: No over current polarity defined

By the way, fix over-current detection on usbotg port for prtvt7, prti6q
and prtwd2 boards. Only prtrvt do not have OC on USB OTG port.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6dl-prtrvt.dts

@@ -124,6 +124,10 @@ &usbh1 {
 	status = "disabled";
 };
 
+&usbotg {
+	disable-over-current;
+};
+
 &vpu {
 	status = "disabled";
 };

arch/arm/boot/dts/imx6qdl-prti6q.dtsi

@@ -69,6 +69,7 @@ &usbh1 {
 	vbus-supply = <&reg_usb_h1_vbus>;
 	phy_type = "utmi";
 	dr_mode = "host";
+	disable-over-current;
 	status = "okay";
 };
 
@@ -78,10 +79,18 @@ &usbotg {
 	pinctrl-0 = <&pinctrl_usbotg>;
 	phy_type = "utmi";
 	dr_mode = "host";
-	disable-over-current;
+	over-current-active-low;
 	status = "okay";
 };
 
+&usbphynop1 {
+	status = "disabled";
+};
+
+&usbphynop2 {
+	status = "disabled";
+};
+
 &usdhc1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_usdhc1>;