Add tx offload functions for wx_xmit_frame_ring which
includes wx_encode_tx_desc_ptype, wx_tso and wx_tx_csum.
which supports ngbe and txgbe to implement tx offload
function.
Signed-off-by: Mengyuan Lou <mengyuanlou@net-swift.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>