Build ed on amd64. The pci attachment works with qemu on amd64.

I'm holding off on building on sparc64 and others because I don't know
if this driver has had all the inb/outb removed (I think it has). Nor
do I know if there are byte ordering issues. There are very few word
operations on an NE2000, but I've not had time to audit them all.

Suggested by: Daniel O'Connor