net/mlx5e: TC, Add support to offload sample action

net/mlx5e: TC, Add support to offload sample action

The following diagram illustrates the hardware model for tc sample action:

        +---------------------+
        + original flow table +
        +---------------------+
        +   original match    +
        +---------------------+
                   |
                   v
+------------------------------------------------+
+                Flow Sampler Object             +
+------------------------------------------------+
+                    sample ratio                +
+------------------------------------------------+
+    sample table id    |    default table id    +
+------------------------------------------------+
           |                            |
           v                            v
+-----------------------------+  +----------------------------------------+
+        sample table         +  + default table per <vport, chain, prio> +
+-----------------------------+  +----------------------------------------+
+ forward to management vport +  +            original match              +
+-----------------------------+  +----------------------------------------+
                                 +            other actions               +
                                 +----------------------------------------+

The sample action is translated to a goto flow table object
destination which samples packets according to the provided
sample ratio. Sampled packets are duplicated. One copy is
processed by a termination table, named the sample table,
which sends the packet to the eswitch manager port (that will
be processed by software).

The second copy is processed by the default table which executes
the subsequent actions. The default table is created per <vport,
chain, prio> tuple as rules with different prios and chains may
overlap.

Signed-off-by: Chris Mi <cmi@nvidia.com>
Reviewed-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>