Realtek PWM Controller

Required properties:
- compatible: "realtek,rts3903-pwm"
- reg: Address range of the PWM registers
- pinctrl-names: Set to "default"
- pinctrl-0: List of phandles pointing to pin configuration nodes
  for PWM module.

Example:

	pwm: pwm@0x18820000 {
		compatible = "realtek,rts3903-pwm";
		reg = <0x18820000 0x10000>;
		pinctrl-names = "default";
		pinctrl-0 = <&pwm_default_mode>;
		status = "disabled";
	};
