net/mlx5e: IPsec: Fix crypto offload for non TCP/UDP encapsulated traffic

IPsec crypto offload always set the ethernet segment checksum flags with
the inner L4 header checksum flag enabled for encapsulated IPsec offloaded
packet regardless of the encapsulated L4 header type, and even if it
doesn't exists in the first place, this breaks non TCP/UDP traffic as
such.

Set the inner L4 checksum flag only when the encapsulated L4 header
protocol is TCP/UDP using software parser swp_inner_l4_offset field as
indication.

Fixes: 5cfb540e

 ("net/mlx5e: Set IPsec WAs only in IP's non checksum partial case.")
Signed-off-by: Raed Salem <raeds@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>