net/mlx4_en: Remove unused argument in TX datapath function

Remove owner argument, as it is obsolete and unused.
This also saves the overhead of calculating its value in data-path.

Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Saeed Mahameed <saeedm@mellanox.com>
Cc: kernel-team@fb.com
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>