Comment 2 for bug 1554236

For ICMPv6 destination unreachable messages, the packet trapped to agent for flow processing has incorrect source-port and destination port values. ICMP-id should be source port, but instead the source-port is ICMP6_TYPE_ECHO_REPLY (129). ICMP6_TYPE_ECHO_REPLY should be destination port, but instead destination-port is ICMP-id.