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_start)()
to take a struct ifnet *, rather than a unit number.
remove their 'integrate' (usually defined to be 'static') keywords.
when lance drivers are split up by attachment, more than one file will
reference the copy/zero functions (i.e. not just the file that pulls in
am7990.c... and eventually inclusion of am7990.c should go away entirely).
if the CPP symbols LE_TINT_HOOK and LE_RINT_HOOK are defined, respectively.
The hooks are called by jumping though the sc_tint_hook and sc_rint_hook
members of the softc, and take the softc as an argument. Only ports which
need these hooks need to declare them in the softc.
thorpej