Enable DT based probing of the vibra driver.

Example of dts section to load the twl6040-vibra driver:
twl6040: twl6040@4b {
	...
	twl6040_vibra: twl6040@1 {
		compatible = "ti,twl6040-vibra";
		interrupts = <4>;
		vddvibl-supply = <&vbat>;
		vddvibr-supply = <&vbat>;
		vibldrv_res = <8>;
		vibrdrv_res = <3>;
		viblmotor_res = <10>;
		vibrmotor_res = <10>;
	};
};

[Sasha Levin <levinsasha928@gmail.com>: fixed build error]
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>