iwlwifi: mvm: support station type API

Support change to ADD_STA API to support station types.
Each station is assigned its type.
This simplifies FW handling of the broadcast and multicast
stations:
* broadcast station is identified by its type and not the mac
  address.
* multicast queue is no longer treated differently. The opening
  and closing of it is done by referring to its station.
  There is no need to specify it in the MAC command.
* When disabling TX to all station driver can disable the traffic
  on multicast station, so FW doesn't have to do it.
Change is backward compatible.
Change the order of adding and removing the stations according to
FW requirements.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>