QCA Pulse Width Modulation (PWM)

Required properties:
- compatible : Should contain "qca,ipq4019-pwm".
- clock : Should contain the input clock.
- clock-names : Should contain "core".
- pwm-base-index : The base index to be used for the pwm device.
	Should contain any unsigned integer.
- used-pwm-indices : Vector specifying the devices that are being used.
	Should contain a boolean entry for each pwm device in the chip
	specifying whether the device is being used or not.
		Example: used-pwm-indices = <1>, <1>, <0>, <1>;
	This chip has 4 pwm devices of which the third one is not used.