the only architecture dependence of devether was enabling interrupts,
which is now done at the end of the driver's reset() function now.
the wifi stack and dummy ethersink also go to port/.
do the IRQ2->IRQ9 hack for pc kernels in intrenabale(), so not
every caller of intrenable() has to be aware of it.
- drivers enable short preamble and sort timeslot depending
on the ap beacon capinfo field (bss->cap)
- wifi sets short preamble bit in capinfo on association request
- wifi sets short timeslot bit when ap advertized it in beacon
introduce wificfg() function to convert ether->opt[] strings
to wifictl messages, which needs quoting for the value. so
etherX=type=iwl essid='something with spaces' works.