dt-bindings: iio: temperature: Add support for tmp006

Add devicetree binding document for TMP006, IR thermopile sensor.

Signed-off-by: Anup Sharma <anupnewsmail@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/3bbda3b1402a26cdafc95c7685679f2311365cad.1684579603.git.anupnewsmail@gmail.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>