Wi-SUN NS NUD & Probe send update

Simplify Probe parent check for Border router it save a code size.

Stop send NUD if device is not ARO registred child or proper parent candidate.

Change-Id: I197e45b47ed35da950631de2747eb8f4425e380b

Author: Juha Heiskanen

source/6LoWPAN/ws/ws_bootstrap.c

@@ -1498,8 +1498,19 @@ static bool ws_neighbor_entry_nud_notify(mac_neighbor_table_entry_t *entry_ptr,
         return false;
     }
 
+    uint8_t ll_address[16];
+
     if (time_from_start > WS_NEIGHBOR_NUD_TIMEOUT) {
 
+        ws_bootsrap_create_ll_address(ll_address, entry_ptr->mac64);
+
+        if (!rpl_control_is_dodag_parent_candidate(cur, ll_address, WS_NEIGHBOUR_MAX_CANDIDATE_PROBE)) {
+            if (!ipv6_neighbour_has_registered_by_eui64(&cur->ipv6_neighbour_cache, entry_ptr->mac64)) {
+                //NUD Not needed for if neighbour is not child or parent candidate
+                return false;
+            }
+        }
+
         if (time_from_start > WS_NEIGHBOR_NUD_TIMEOUT * 1.5) {
             activate_nud = true;
         } else {
@@ -1518,14 +1529,10 @@ static bool ws_neighbor_entry_nud_notify(mac_neighbor_table_entry_t *entry_ptr,
             //Accept quick Probe for init ETX
             activate_nud = true;
         } else {
-            if (cur->bootsrap_mode == ARM_NWK_BOOTSRAP_MODE_6LoWPAN_BORDER_ROUTER) {
-                return false; // Border router never probe automatically
-            } else {
-                uint8_t ll_address[16];
-                ws_bootsrap_create_ll_address(ll_address, entry_ptr->mac64);
-                if (!rpl_control_is_dodag_parent_candidate(cur, ll_address, WS_NEIGHBOUR_MAX_CANDIDATE_PROBE)) {
-                    return false;
-                }
+
+            ws_bootsrap_create_ll_address(ll_address, entry_ptr->mac64);
+            if (!rpl_control_is_dodag_parent_candidate(cur, ll_address, WS_NEIGHBOUR_MAX_CANDIDATE_PROBE)) {
+                return false;
             }
 
             uint32_t probe_period = WS_PROBE_INIT_BASE_SECONDS << etx_entry->etx_samples;