[LinuxBIOS] Add support for Via vt82c686a

[Corey Osgood]

Please scratch the patch I submitted. vt82c686a and b are the same, the 
docs lied (and this is the first time I've looked at it on the machines, 
stupid me). I'm reworking a few things and cleaning up a few more 
things, and I'll submit a working, tested patch this weekend, if all 
goes well.

On a related note, does anyone know if any northbridge init is required 
to bring up the southbridge (and in this case also superio)? And is the 
rcn dc1100s from v1 working or not? I couldn't get it to run (no serial 
or video output at all) on the tyan s2507, which seems to be the same 
hardware.