Removed rank comprae and also probe 5 best on the list.

Change-Id: Iaf1d58e541c0f793d11c5f4ec4fa03faf7575795

Author: Juha Heiskanen

source/RPL/rpl_upward.c

@@ -1638,16 +1638,7 @@ bool rpl_instance_address_is_candidate(rpl_instance_t *instance, const uint8_t *
 
     ns_list_foreach(rpl_neighbour_t, neighbour, &instance->candidate_neighbours) {
         if (addr_ipv6_equal(neighbour->ll_address, ipv6_addr)) {
-
-            if (!instance->current_dodag_version) {
-                return true;
-            }
-
-            if (rpl_rank_compare(instance->current_dodag_version->dodag, neighbour->rank, instance->current_rank) & RPL_CMP_LESS) {
-                return true;
-            }
-
-            return false;
+            return true;
         }
         list_compared++;
         if (candidate_amount && list_compared >= candidate_amount) {