iio: temperature: add driver support for ti tmp117

TMP117 is a Digital temperature sensor with integrated Non-Volatile memory.
Add support for tmp117 driver in iio subsystem.

Datasheet: https://www.ti.com/lit/gpn/tmp117


Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20210407182147.77221-3-puranjay12@gmail.com


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