net/mlx5: Add DCS caps & fields support

This fields will be needed when adding a support for DCS offload

max_dci_stream_channels - maximum DCI stream channels supported per DCI.
max_dci_errored_streams - maximum DCI error stream channels
supported per DCI before a DCI move to error state.

Signed-off-by: Lior Nahmanson <liorna@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>