For ip4 tcp, ip6 tcp, and ip6 udp packet, we set checksum = 0 prior to
computing the checksum. We missed ip4 udp case. This oversight requires all
clients to set udp->checksum = 0 if ip4 udp checksum offload is needed.
Type: fix
Signed-off-by: Steven Luong <sluong@cisco.com>
Change-Id: Ic608811e82099f3bec469e123671e9b281f38d76