Amazon's Annapurna Labs Thermal Sensor

Simple thermal device that allows temperature reading by a single MMIO
transaction.

Required properties:
- compatible: "amazon,al-thermal".
- reg: The physical base address and length of the sensor's registers.
- #thermal-sensor-cells: Must be 1. See ./thermal.txt for a description.

Example:
	thermal: thermal {
		compatible = "amazon,al-thermal";
		reg = <0x0 0x05002860 0x0 0x1>;
		#thermal-sensor-cells = <0x1>;
	};

	thermal-zones {
		thermal-z0 {
			polling-delay-passive = <250>;
			polling-delay = <1000>;
			thermal-sensors = <&thermal 0>;
			trips {
				critical {
					temperature = <105000>;
					hysteresis = <2000>;
					type = "critical";
				};
			};

		};
	};