net/ice: calculate TCP header size for offload
net/ice: calculate TCP header size for offload

The ice needs the exact TCP header size including options for TCP
checksum offload, but according to PKT_TX_TCP_CKSUM note, l4_len
is not required to be set, so it needs to calculate the TCP header
size if not set.

Fixes: 17c7d0f9d6a4 ("net/ice: support basic Rx/Tx")
Cc: stable@dpdk.org

Signed-off-by: Haiyue Wang <037d5f2d0d83548aebdad8ba0c69c0b30ec44c86@intel.com>
Acked-by: Qi Zhang <9e9e58ffa71a29bb7b87766b362515be648fcbe0@intel.com>
Acked-by: Qiming Yang <6f20802c8a43e38f9b475618bd31b5b1ac8c8656@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk