net/mlx5e: Drop error CQE handling from the XSK RX handler

This commit removes the redundant check and removes the unused cqe parameter
of skb_from_cqe handlers.

Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>