Change beacon filtering command due to a change in the API.

In case the FW supports the old API, we do not send the
BF HCMD and assume that since the corresponding struct in
the FW is zeroed by default then we don't need to disable
it in the FW actively.
Signed-off-by: Hila Gonen <hila.gonen@intel.com>
Signed-off-by: Dor Shaish <dor.shaish@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>