[RFC] VIA south bridge watchdog support

[Fabien Thomas]

> 	Hi,
> 
> If someone want to look at I've added support for VIA south bridge watchdog.
> It has been tested on VX900 but should works with VX800, VX855, CX700.
> 
> http://people.freebsd.org/~fabient/patch-watchdog-via-rev1
> 

Posted rev2 : http://people.freebsd.org/~fabient/patch-watchdog-via-rev2
- add / test VT8251
- man page update
- reset FIRED bit when detected

Maybe other south bridge supported but feedback is needed.

Fabien