WRPC did now check destination IP address of incoming packets. By this WRPC
responded to the incoming packets regardless of destination IP.
It may generate an error when two nodes with the same MAC are connected to
the same network. It can happen when nodes fail to generate unique MAC.
It was observed that SNMP packets were forwarded randomly to two nodes.
Signed-off-by: Adam Wujek <adam.wujek@cern.ch>