[Open-graphics] Jumper count to disconnect DDC from DVI connector

[Dieter]

>    To answer an earlier question: if we want to include a feature on OGC1 to disconnect the DDC signals from the DVI conne
>ctor so that the external tool will have control of those signals, only two lines need to be disconnected: SCL and SDA.  So
> the cost impact of doing it with jumper plugs would be minimal.

If Jack's design is used, (and if I understand it correctly) I think we
could look for a signal on the aux DDC, and if one is found then use it,
If no signal is found on the aux DDC, then look for a signal on the
DVI's DCC pins.  If this scheme works, then we don't need jumpers for DDC.