Rockchip internal OTP (One Time Programmable) memory device tree bindings

Required properties:
- compatible: Should be one of the following.
  - "rockchip,px30-otp" - for PX30 SoCs.
  - "rockchip,rk3308-otp" - for RK3308 SoCs.
- reg: Should contain the registers location and size
- clocks: Must contain an entry for each entry in clock-names.
- clock-names: Should be "otp", "apb_pclk" and "phy".
- resets: Must contain an entry for each entry in reset-names.
  See ../../reset/reset.txt for details.
- reset-names: Should be "phy".

See nvmem.txt for more information.

Example:
	otp: otp@ff290000 {
		compatible = "rockchip,px30-otp";
		reg = <0x0 0xff290000 0x0 0x4000>;
		#address-cells = <1>;
		#size-cells = <1>;
		clocks = <&cru SCLK_OTP_USR>, <&cru PCLK_OTP_NS>,
			 <&cru PCLK_OTP_PHY>;
		clock-names = "otp", "apb_pclk", "phy";
	};
