Stop sending normal ACK if neighbour is Unknown.

Change-Id: If2259947559df2bf3df685ec5741f6c8ef467b11

Author: Juha Heiskanen

source/6LoWPAN/ws/ws_llc_data_service.c

@@ -560,7 +560,7 @@ static void ws_llc_mac_indication_cb(const mac_api_t *api, const mcps_data_ind_t
 
         if (!base->ws_neighbor_info_request_cb(interface, data->SrcAddr, &neighbor_info, request_new_entry)) {
             if (!multicast || ws_utt.message_type == WS_FT_EAPOL) {
-                tr_debug("Drop message no neighbor");
+                //tr_debug("Drop message no neighbor");
                 return;
             } else {
                 //Allocate temporary entry

source/MAC/IEEE802_15_4/mac_pd_sap.c

@@ -772,7 +772,7 @@ static int8_t mac_pd_sap_generate_ack(protocol_interface_rf_mac_setup_s *rf_ptr,
         return -1;
     }
 
-    if (rf_ptr->enhanced_ack_buffer.aux_header.securityLevel == 0 || mac_sec_mib_device_description_get(rf_ptr, rf_ptr->enhanced_ack_buffer.DstAddr, rf_ptr->enhanced_ack_buffer.fcf_dsn.DstAddrMode, rf_ptr->enhanced_ack_buffer.DstPANId)) {
+    if (mac_sec_mib_device_description_get(rf_ptr, rf_ptr->enhanced_ack_buffer.DstAddr, rf_ptr->enhanced_ack_buffer.fcf_dsn.DstAddrMode, rf_ptr->enhanced_ack_buffer.DstPANId)) {
         rf_ptr->ack_tx_possible = true;
     } else {
         rf_ptr->ack_tx_possible = false;