o add back rx monitor support
o make WI_RID_SCAN_RES DTRT
o fix a bug handling zero-length RID requests (used by dstumbler to set
a zero-length SSID)
o make RID_SCAN_REQ DTRT
o add back WI_RID_OWN_SSID
o fix wi_scan_ap to take a channel mask and txrate (for prism cards)
These changes fix dstumbler -o (monitor mode). A minor change to dstumbler
is needed to get normal AP scanning mode to work right; this is preferred to
modifying the driver.
PR: kern/53187
Reviewed by: Bruce M Simpson <bms@spc.org>