* Fiq debugger based on UART

- compatible: "rockchip,fiq-debugger"

  Compatibility with all rk30xx rk31xx rk32xx rk33xx SOCs.

- rockchip,serial-id: The uart which is used as debug port,
  start from 0,1,2,3...

- rockchip,signal-irq: A hardware interrupt without source,
  which is triggered by FIQ handler to call functions that
  must be called in IRQ context. Often it is configured by
  soc developer.

- rockchip,wake-irq: It is used to wake up fiq debugger,
  but usually not used.

- rockchip,irq-mode-enable: If it is set 1, uart uses irq
  instead of fiq.

- rockchip,baudrate: Only 115200 and 1500000.

Example:
	fiq-debugger {
		compatible = "rockchip,fiq-debugger";
		rockchip,serial-id = <2>;
		rockchip,signal-irq = <186>;
		rockchip,wake-irq = <0>;
		rockchip,irq-mode-enable = <0>;
		rockchip,baudrate = <115200>;
		status = "disabled";
	};