naming conflicts between bus attachments on ports that can have
multiple instances of the LANCE.
Changed struct ifnet to have a pointer to the softc of the underlying
device and a printable "external name" (name + unit number), thus eliminating
if_name and if_unit. Updated interface to (*if_watchdog)() and (*if_reset)()
to take a struct ifnet *, rather than a unit number.
should work properly with:
(1) LANCE chips hanging off the system IOCTL asic,
(2) LANCE chips TurboChannel option boards.
Support for various PMAX-family baseboard options isn't yet in this
file, but should be easy to add.