hwmon: (dme1737) fix voltage scaling

This patch fixes a voltage scaling issue for the sch311x device.

Signed-Off-By: Juerg Haefliger <juergh at gmail.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>