o change rssi to be signed in ieee80211_nodestats
o add noise floor in ieee80211_nodestats (use an implicit hole to
preserve layout); return it as zero until we can update the api's
so the driver can provide noise floor data
o add a bandaid so IEEE80211_IOC_STA_STATS works for sta mode; when
all nodes are in the station table this will no longer be needed
o fix braino in IEEE80211_IOC_STA_INFO implementation; was supposed
to take a mac address and return info for that sta or all stations
if ff:ff:ff:ff:ff was supplied--but somehow this didn't get implemented;
implement the intended semantics and leave a compat shim at the old
ioctl number for the previous api
Reviewed by: mlaier
MFC after: 3 weeks
f478fb3344