iwlwifi: mvm: Add support for additional addresses

Use the number of addresses (max 5) from the NVM
instead of limiting to 2 artificially.

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>