Binding for UNIVERSAL Charger

Required properties:
- compatible: Should contain one of the following:
    * "universal-charger"
- extcon: extcon specifier for the Charger.
- dc-det-gpio: gpio for dc detect.

Example:

	universal_charger {
		status = "okay";
		compatible = "universal-charger";
		extcon = <&u2phy0>;
		dc-det-gpio = <&gpio3 1 GPIO_ACTIVE_HIGH>;
	};