SMSC USB3503 High-Speed Hub Controller

Required properties:
- compatible: Should be "smsc,usb3503".
- reg: Specifies the i2c slave address, it should be 0x08.
- connect-gpios: Should specify GPIO for connect.
- intn-gpios: Should specify GPIO for interrupt.
- reset-gpios: Should specify GPIO for reset.
- initial-mode: Should specify initial mode.
                (1 for HUB mode, 2 for STANDBY mode)

Examples:
	usb3503@08 {
		compatible = "smsc,usb3503";
		reg = <0x08>;
		connect-gpios = <&gpx3 0 1>;
		intn-gpios = <&gpx3 4 1>;
		reset-gpios = <&gpx3 5 1>;
		initial-mode = <1>;
	};
