* NXP PCF8523 Real Time Clock

Required properties:
- compatible: Should contain "nxp,pcf8523".
- reg: I2C address for chip.

Optional property:
- quartz-load-femtofarads: The capacitive load of the quartz(x-tal),
  expressed in femto Farad (fF). Valid values are 7000 and 12500.
  Default value (if no value is specified) is 12500fF.

Example:

pcf8523: rtc@68 {
	compatible = "nxp,pcf8523";
	reg = <0x68>;
	quartz-load-femtofarads = <7000>;
};