Spreadtrum SC27xx PMIC Vibrator

Required properties:
- compatible: should be "sprd,sc2731-vibrator".
- reg: address of vibrator control register.

Example :

	sc2731_pmic: pmic@0 {
		compatible = "sprd,sc2731";
		reg = <0>;
		spi-max-frequency = <26000000>;
		interrupts = <GIC_SPI 31 IRQ_TYPE_LEVEL_HIGH>;
		interrupt-controller;
		#interrupt-cells = <2>;
		#address-cells = <1>;
		#size-cells = <0>;

		vibrator@eb4 {
			compatible = "sprd,sc2731-vibrator";
			reg = <0xeb4>;
		};
	};