* Amlogic Meson6, Meson8, Meson8b and Meson8m2 RTC

Required properties:
- compatible: should be one of the following describing the hardware:
	* "amlogic,meson6-rtc"
	* "amlogic,meson8-rtc"
	* "amlogic,meson8b-rtc"
	* "amlogic,meson8m2-rtc"

- reg: physical register space for the controller's memory mapped registers.
- interrupts: the interrupt line of the RTC block.
- clocks: reference to the external 32.768kHz crystal oscillator.
- vdd-supply: reference to the power supply of the RTC block.
- resets: reset controller reference to allow reset of the controller

Optional properties for the battery-backed non-volatile memory:
- #address-cells: should be 1 to address the battery-backed non-volatile memory
- #size-cells: should be 1 to reference the battery-backed non-volatile memory

Optional child nodes:
- see ../nvmem/nvmem.txt

Example:

	rtc: rtc@740 {
		compatible = "amlogic,meson6-rtc";
		reg = <0x740 0x14>;
		interrupts = <GIC_SPI 72 IRQ_TYPE_EDGE_RISING>;
		clocks = <&rtc32k_xtal>;
		vdd-supply = <&rtc_vdd>;
		resets = <&reset RESET_RTC>;

		#address-cells = <1>;
		#size-cells = <1>;
	};