net/mlx5: Remove indirection in TLS build

The dream described in the commit 1ae17322 ("net/mlx5: Accel, Add TLS
tx offload interface") never came true, even an opposite happened when FPGA
TLS support was dropped. Such removal revealed the problematic flow in the
build process: build of unrelated files in case of TLS or IPsec are enabled.

In both cases, the MLX5_ACCEL is enabled, which built both TLS and IPsec.
As a solution, simply merge MLX5_TLS and MLX5_EN_TLS options and move TLS
related files to the eth part of the mlx5_core.

Link: https://lore.kernel.org/r/0d1ea8cdc3a15922640b8b764d2bdb8f587b52c2.1649073691.git.leonro@nvidia.com


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