(1) remove the 'UNSUPP' keyword from the device list,
because it can't be reasonably used (becuase different
devices may be supported on different machines, for
good reason).
(2) enhance pci_devinfo so that class/subclass information
is optional (so pci_devinfo can be used by drivers that
match classes of devices, and want to look up the
devices' names easily).
(3) more known vendors and devices.
vendor & product IDs and class information, which is printed if device
isn't found. Optionally (via "PCIVERBOSE" option) does table lookup
to try to see if it knows what the device really is (informational only...).
(pci_attach_subdev()). remove pciattach() function and the pcicd cfdriver
struct, the former because thre are a lot of attachment actions which really
are machine-dependent (perhaps even "most"), and the latter because now that
both pcimatch() and pciattach() are machine-dependent it's bad style to
declare them here and it gains nothing.
