hwmon: Fix more __devexit_p glitches

Make sure __devexit and devexit_p() match in all hwmon drivers.
Suggested by a similar fix from Mike Frysinger.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>