hwmon: Driver for TI TMP103 temperature sensor

Driver for the TI TMP103.

The TI TMP103 is similar to the TMP102.  It differs from the TMP102
by having only 8 bit registers.

Signed-off-by: Heiko Schocher <hs@denx.de>
[linux@roeck-us.net: Select REGMAP_I2C in Kconfig]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>