hwmon: (tmp401) Add support for TI's TMP401 sensor chip

This is a new hwmon driver for TI's TMP401 temperature sensor IC. This driver
was written on behalf of an embedded systems vendor under the
Linux driver project.

It has been tested using a TI TMP401 sample attached to a i2c-tiny-usb adapter.
Which was provided by Till Harbaum, many thanks to him for this!

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>