net/sfc: fix TSO and checksum offloads for EF10

net/sfc: fix TSO and checksum offloads for EF10

This is workaround for 8000-series EF10 hardware TSO bug.
Innermost IP length and outer UDP datagram length must be
greater than or equal to the corresponding values derived
from the MSS; otherwise, the checksum offloads will break.

Fixes: c1ce2ba218f8 ("net/sfc: support tunnel TSO on EF10 native Tx datapath")
Fixes: 6bc985e41155 ("net/sfc: support TSO in EF10 Tx datapath")
Fixes: fec33d5bb3eb ("net/sfc: support firmware-assisted TSO")
Cc: stable@dpdk.org
Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Reviewed-by: Andy Moreton <amoreton@xilinx.com>