hwmon: (f75375s) Drop legacy i2c driver

Drop the legacy f75375s i2c driver, and add a detect callback to the
new-style i2c driver to achieve the same functionality.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Riku Voipio <riku.voipio@movial.fi>