Currently, detection in hwsim and ath9k can
detect that two sw scans are in flight at the
same time, which isn't really true. It is
caused by a race condition, because the scan
complete callback is called too late, after
the lock has been dropped, so that a new scan
can be started before it is called.

It is also called too early semantically, as
it is currently called _after_ the return to
the operating channel -- it should be before
so that drivers know this is the operating
channel again.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>