Realtek SARADC Controller

Required properties:
- compatible: "realtek,rts3903-saradc"
- reg: Address range of the saradc registers

Example:

	saradc: saradc@0x18840000 {
		compatible = "realtek,rts3903-saradc";
		reg = <0x18840000 0x10000>;
		status = "disabled";
	};
