net/mlx5e: TX, Inline function mlx5e_tls_handle_tx_wqe()

When TLS is supported, WQE ctrl segment of every transmitted packet
is updated with the (possibly empty, for non-TLS packets) TISN field.

Take this one-liner function into the header file and inline it,
to save the overhead of a function call per packet.

While here, remove unused function parameter.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>