MXS regulators

Required properties:
- compatible		: Must be "digi,mxs-regulator".
- regulator-type:       : "current" or "voltage"

Optional properties:
- mxs-regulator-brown-out: Specifies a brown out voltage regulator.

Any property defined as part of the core regulator binding defined in
regulator.txt can also be used.

Example:

        vddd@80044040 {
                compatible = "digi,mxs-regulator";
                reg = <0x80044040 0x10>;
                regulator-name = "vddd";
                regulator-min-microvolt = <800000>;
                regulator-max-microvolt = <1575000>;
                regulator-type = "voltage";
                regulator-always-on;
};
