net/mlx5e: Remove ethernet segment from dump WQE

Dump WQE shall not include Ethernet segment. Define mlx5e_dump_wqe to be
used for "Dump WQEs" instead of sharing it with the general mlx5e_tx_wqe
layout.

Fixes: d2ead1f3 ("net/mlx5e: Add kTLS TX HW offload support")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>