net/mlx5: Prepare for fast crypto key update if hardware supports it

Add CAP for crypto offload, do the simple initialization if hardware
supports it. Currently set log_dek_obj_range to 12, so 4k DEKs will be
created in one bulk allocation.

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