Allwinner sun8i-v536 SoC PWM controller

Required properties:
 - compatible: should be "allwinner,<name>-pwm"
   "allwinner,sun8i-v833-pwm"
   "allwinner,sun8i-v536-pwm"
   "allwinner,sun50i-r818-pwm"
   "allwinner,sun50i-a133-pwm"
   "allwinner,sun50i-r329-pwm"
 - reg: physical base address and length of the controller's registers
 - #pwm-cells: should be 3. See pwm.txt in this directory for a description of
   the cells format.
 - clocks: From common clock binding, handle to the parent clock.
 - resets: From reset clock binding, handle to the parent clock.

Example:

	pwm: pwm@300a0000 {
		compatible = "allwinner,sun50i-r818-pwm";
		reg = <0x0300a000 0x3ff>;
		clocks = <&ccu CLK_BUS_PWM>;
		resets = <&ccu RST_BUS_PWM>;
		#pwm-cells = <3>;
	};
