SKY81452 bindings

Required properties:
- compatible	: Must be "skyworks,sky81452"
- reg		: I2C slave address

Required child nodes:
- backlight	: container node for backlight following the binding
		in video/backlight/sky81452-backlight.txt
- regulator	: container node for regulators following the binding
		in regulator/sky81452-regulator.txt

Example:

	sky81452@2c {
		compatible = "skyworks,sky81452";
		reg = <0x2c>;

		backlight {
			compatible = "skyworks,sky81452-backlight";
			name = "pwm-backlight";
			led-sources = <0 1 2 3 6>;
			skyworks,ignore-pwm;
			skyworks,phase-shift;
			skyworks,current-limit = <2300>;
		};

		regulator {
			lout {
				regulator-name = "sky81452-lout";
				regulator-min-microvolt = <4500000>;
				regulator-max-microvolt = <8000000>;
			};
		};
	};

Add new SKY81452 mfd binding
devicetree: Add new SKY81452 mfd binding

Signed-off-by: Gyungoh Yoo <4577c429a84c451aecfba3008fca6db32773fa63@skyworksinc.com>
Signed-off-by: Lee Jones <630e34333487a351a857f6b705e04d30b37c1629@linaro.org>
