net/mlx5e: Support SWP-mode offload L4 csum calculation

net/mlx5e: Support SWP-mode offload L4 csum calculation

Calculate the pseudo-header checksum for both IPSec transport mode and
IPSec tunnel mode for mlx5 devices that do not implement a pure hardware
checksum offload for L4 checksum calculation. Introduce a capability bit
that identifies such mlx5 devices.

Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20240613210036.1125203-7-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>