* Samsung's adc controller

Required properties:
  - compatible: value should be any of the following.
      (a) "samsung,s3c24xx-adc", for adc compatible with s3c24xx adc.
      (b) "samsung,s3c2443-adc", for adc compatible with s3c2443 adc.
      (c) "samsung,s3c2416-adc", for adc compatible with s3c2416 adc.
      (d) "samsung,s3c64xx-adc", for adc compatible with s3c64xx adc.
      (e) "samsung,exynos4-adc", for adc compatible exynos4 adc.
      (f) "samsung,exynos5-adc", for adc compatible exynos5 adc.
  - reg: physical base address of the controller and length of memory mapped
    region.
  - interrupts: interrupt number to the cpu.

Example:
	adc@12D10000 {
		compatible = "samsung,exynos5-adc";
		reg = <0x12D10000 0x100>;
		interrupts = <0 106 0>;
		vdd-supply = <&buck5_reg>;
	};
