hwmon: (dme1737) No vid attributes for SCH311x

The SCH311x chips do not have VID inputs, so the cpu0_vid and vrm
attributes shouldn't be created for them.

This fixes lm-sensors ticket #2353:
http://www.lm-sensors.org/ticket/2353

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Udo van den Heuvel <udovdh@xs4all.nl>
Cc: Juerg Haefliger <juergh@gmail.com>