Prometheus PCI support

[Radoslaw Kujawa <radoslaw.kujawa%c0ff33.net@localhost>]

Hi list.

I've completed the Prometheus PCI driver. In theory, every non-DMA PCI card 
driver should work now. The driver will be committed as soon as Frank review 
it. 

http://c0ff33.net/drop/prometheus-ne.jpg

The only thing left to implement is bus enumeration and assigning resources to 
the cards (PCI_NETBSD_CONFIGURE option). It is needed for bootblock users, as 
Prometheus does not have any firmware and this work is usually done by 
prometheus.library in AmigaOS. 

There's still unresolved annoyance with M68K_PTBASE. The default value is far 
too low for machines with Prometheus (which is a 512MB Z3 I/O board). I could 
just add information to man page, that the Prometheus user should increase it. 
But that's not an user friendly solution… 

--
Best regards,
Radoslaw Kujawa