Update the scan command API with support for adaptive dwell.  Adaptive
dwell is a type of scan that dynamically changes the time it remains
on each channel listening for beacons or probe responses.
Signed-off-by: NRoee Zamir <roee.zamir@intel.com>
Signed-off-by: NBeni Lev <beni.lev@intel.com>
Signed-off-by: NLuca Coelho <luciano.coelho@intel.com>