nl80211: Cancel not yet started r-o-c

nl80211: Cancel not yet started r-o-c

Currently, the following can happen:

1) P2P state machine requests R-O-C
2) user changes their mind and aborts
3) P2P state machine aborts R-O-C
4) driver_nl80211 rejects abort since there
   was no notification about the start yet
5) R-O-C period start notification from kernel
6) P2P state machine requests new R-O-C
7) this overlaps with old R-O-C -- iwlwifi driver
   can't handle that and returns -EBUSY
8) state machine stops dead in its tracks

The reason is that the abort isn't going through properly. Instead of
tracking whether a R-O-C is active in driver_nl80211, track whether one
was requested to avoid this scenario.

Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>