* STMP3xxx/i.MX28 Time Clock controller

Required properties:
- compatible: should be one of the following.
    * "fsl,stmp3xxx-rtc"
- reg: physical base address of the controller and length of memory mapped
  region.
- interrupts: rtc alarm interrupt

Optional properties:
- stmp,crystal-freq: override crystal frequency as determined from fuse bits.
  Only <32000> and <32768> are possible for the hardware.  Use <0> for
  "no crystal".

Example:

rtc@80056000 {
	compatible = "fsl,imx28-rtc", "fsl,stmp3xxx-rtc";
	reg = <0x80056000 2000>;
	interrupts = <29>;
};
