AKM AK8963 3-axis electronic compass driver

Required properties:

 - compatible		: Should be "ak,ak8963".
 - reg			: i2c address of the device.
 - pinctrl-names	: The pinctrl configration names of this sensor driver. Should be "ak8963_default".
 - pinctrl-0		: The pinctrl node corresponding to "ak8963_default", should be <&ak8963_default>.
 - interrupt-parent	: Parent of interrupt.
 - interrupts		: Ecompass interrupt to indicate new data ready.
 - vdd-supply		: Analog power supply needed to power up the device.
 - vio-supply		: Digital IO power supply needed for IO and I2C.
 - ak,layout		: The layout of the ecompass sensor chip. There are 8
	patterns of layout described as below:
	0: Indicate the invalid pattern, The userspace will decide the pattern.
	1: 1st pin is right down
	2: 1st pin is left down
	3: 1st pin is left top
	4: 1st pin is right top
	5: 1st pin is left down (from top view)
	6: 1st pin is left top (from top view)
	7: 1st pin is right top (from top view)
	8: 1st pin is right down (from top view)

Optional properites:
 - ak,gpio_rstn		: The gpio pin to reset the sensor chip.
 - ak,auto-report	: Enable auto-report mode.
 Example:
	akm@c {
			compatible = "ak,ak8963";
			reg = <0x0c>;
			pinctrl-names = "ak8963_default";
			pinctrl-0 = <&ak8963_default>;
			interrupt-parent = <&msm_gpio>;
			interrupts = <69 0x2>;
			vdd-supply = <&pm8916_l17>;
			vio-supply = <&pm8916_l6>;
			ak,layout = <0x0>;
			ak,gpio_rstn = <&msm_gpio 82 0x0>;
			ak,auto-report;
	};