iwlwifi: mvm: Update MAC context filter flags

1. For P2P Device filter in only probe requests.
2. For station mode filter in all group cast frames,
   and in addition beacons as long as we are not associated.
3. For AP/GO filter in all group cast and in addition probe
   requests.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>