dt-bindings: iio: temperature: add MLX90632 device bindings

Add device tree bindings for MLX90632 IR temperature sensor.
Signed-off-by: Crt Mori <cmo@melexis.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/temperature/mlx90632.txt

+* Melexis MLX90632 contactless Infra Red temperature sensor
+
+Link to datasheet: https://www.melexis.com/en/documents/documentation/datasheets/datasheet-mlx90632
+
+There are various applications for the Infra Red contactless temperature sensor
+and MLX90632 is most suitable for consumer applications where measured object
+temperature is in range between -20 to 200 degrees Celsius with relative error
+of measurement below 1 degree Celsius in object temperature range for
+industrial applications. Since it can operate and measure ambient temperature
+in range of -20 to 85 degrees Celsius it is suitable also for outdoor use.
+
+Be aware that electronics surrounding the sensor can increase ambient
+temperature. MLX90632 can be calibrated to reduce the housing effect via
+already existing EEPROM parameters.
+
+Since measured object emissivity effects Infra Red energy emitted, emissivity
+should be set before requesting the object temperature.
+
+Required properties:
+  - compatible: should be "melexis,mlx90632"
+  - reg: the I2C address of the sensor (default 0x3a)
+
+Example:
+
+mlx90632@3a {
+	compatible = "melexis,mlx90632";
+	reg = <0x3a>;
+};