* Pepper comments around which describe what state(s) we're in when faking
up 11n nodes.
* By default don't fake it up as 11n until we properly negotiate the 11n
capabilities using probe request/response frames.
* Send a probe request with our HT information, as the 802.11-2012 spec
suggests.
* Reassociate with the driver if we've been promoted.
This is done because although learning a peer via beacons can learn 11n
state, learning peers via hearing probe frames and broadcast frames
does not. Thus, sometimes you end up with an 11n peer in the peer
table and sometimes you don't.
Note that the probe request/response exchange may not actually succeed.
Ideally we'd put the peer into some blocking state until we've exchanged
probe request/reponse to learn capabilities, or we timeout and just
stay non-11n.
This is more an experiment to get 11n IBSS nodes actually discovering
each other and be able to transmit. There are other issues that creep
up which I'll attempt to address in future commits.
Tested:
* AR9380 NICs in 11n mode.
Reviewed by: avos
Differential Revision: https://reviews.freebsd.org/D8365
869897d2e5