o rework pll setup code to follow h/w specification
o add hint.hifn.X.pllconfig to specify reference clock setup
requirements; default is pci66 which means the clock is
derived from the PCI bus clock and the card resides in a
66MHz slot
Tested on 7955 and 7956 cards; support for 7954 cards not enabled
since we have no cards to test against.
In collaboration with Poul-Henning Kamp.
Reviewed by: phk
MFC after: 1 week
This may not be a generally valid configuration, but neither is relying
on the PCI clock to be stable.
The only currently known and supported hardware is the VPN14x1 from
Soekris, and since it has external clock, we fail safe(r) by using
it.
Unfortunately there is no way to probe this reliably.
