This patch introduces a generic commit() function which initiate a
new network joining process. It should be called after some interface
config changes, so that the changes get applied more cleanly. Currently
set_ssid() and set_bssid() call it. Others can be added in future
patches.

In version 1 the header files was forgotten, sorry.
Signed-off-by: NAlina Friedrichsen <x-alina@gmx.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch splits out the ibss code and data from managed (station) mode.
The reason to do this is to better separate the state machines, and have
the code be contained better so it gets easier to determine what exactly
a given change will affect, that in turn makes it easier to understand.

This is quite some churn, especially because I split sdata->u.sta into
sdata->u.mgd and sdata->u.ibss, but I think it's easier to maintain that
way. I've also shuffled around some code -- null function sending is only
applicable to managed interfaces so put that into that file, some other
functions are needed from various places so put them into util, and also
rearranged the prototypes in ieee80211_i.h accordingly.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>