hwmon: (ltc4245) Clear faults at startup

When power is applied to the ltc4245 chip it sometimes reports spurious
faults, which are exposed as alarms in the hwmon output. Clear the fault
register when the driver is installed to clear the alarms.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Jean Delvare <khali@linux-fr.org>