Richtek RT5081 Vib LDO subdev
RT5081 Vibrator ldo control.

Required properties:
- compatible : Must be "richtek,rt5081_pmu_ldo";
- interrupt-names : RT5081 ldo enabled interrupts.
	(R:required, O:optional)
	1. (O)ldo_oc: report whether the event of LDO over current occurs.

- ldo_oms : ldo oms function, 0 -> floating, 1 -> discharge to ground for off mode.

Optional node:
- ldo_vrc : ldo voltage rampping control.
	    0 -> 1 step/16us, 1 -> 2 steps/16us, 2 -> 4 steps/16us, 3 -> 8 steps/16us.

Child node:
- rt5081_ldo : vib ldo regulator init setting.

Example:
rt5081_pmu@34 {
	status = "ok";
	compatible = "richtek,rt5081_pmu";
	reg = <0x34>;
	interrupt-controller;
	#interrupt-cells = <1>;
	rt,intr_gpio_num = <3>; /* direct defined GPIO num */
	rt,intr_gpio = <&pio 3 0>; /* genernal GPIO */
	ldo {
		compatible = "richtek,rt5081_pmu_ldo";
		interrupt-names = "ldo_oc";
		ldo_oms = <1>; /* 0: floating ; 1: discharge to ground for off mode */
		/* 0:  1 step/16us; 1 : 2 steps/16us; 2: 4 steps/16us; 3: 8steps/16us */
		/*ldo_vrc = <0>; */ /* to assign this  a value will also set en_vrc = 1 */
		ldo_vrc_lt = <1>; /* 0 : disable; 1: 10 us; 2: 20 us; 3: 40 us */
		rt5081_ldo {
			regulator-name = "rt5081_ldo"; /* change name by yourself */
			regulator-min-microvolt = <1600000>;
			regulator-max-microvolt = <4000000>; /* max == min then apply_uV = 1 */
			/* regulator-microvolt-offset = < 0>; optional*/
			/* regulator-boot-on = "yes"; optional, exist = enabled */
			/* regulator-always-on = "yes"; optional, exist = enabled */
			/* regulator-ramp-delay = <100>; optional*/
		};
	};
};
