o lock the list walk
o malloc a results buffer instead of copying out one result at a time
using an on-stack buffer
o fix definition of ieee80211req_scan_result so size of variable-length
information elements is large enough to hold all possible ie's
(still only return wpa+wme, at some point may return all)
o make rssi+noise data signed; they should've been so all along
o add a bit more padding for future additions while we're here
o define a new ioctl for new api and add compat code for old ioctl
under COMPAT_FREEBSD6 (temporarily enabled local to the file)
Reviewed by: Scott Long
MFC after: 2 weeks