data request resent if leader after resync does not receive data response.(#1614)

Author: deepakvenugopal

source/6LoWPAN/Thread/thread_bootstrap.c

@@ -1660,6 +1660,11 @@ bool thread_network_data_timeout(int8_t interface_id, uint16_t msgId, bool usedA
         return true;
     }
 
+    if(cur->thread_info->leader_synced && !usedAllRetries){
+        tr_debug("retrying as leader data not yet synced");
+        return true;
+    }
+
     thread_info(cur)->networkDataRequested = false;
     mac_data_poll_protocol_poll_mode_decrement(cur);
     return false;