void ad_agg_selection_logic (struct aggregator * aggregator);
It is assumed that only one aggregator may be selected for a team. The logic of this function is to select (at first time) the aggregator with the most ports attached to it, and to reselect the active aggregator only if the previous aggregator has no more ports related to it.
this function MUST be called with the first agg in the bond, or __get_active_agg won't work correctly. This function should be better called with the bond itself, and retrieve the first agg from it.