net/mlx5: remove single counter container

net/mlx5: remove single counter container

A flow counter which was allocated by a batch API couldn't be assigned
to a flow in the root table (group 0) in old rdma-core version.
Hence, a root table flow counter required PMD mechanism to manage
counters which were allocated singly.

Currently, the batch counters have already been supported in root table
includes a new rdma-core version with MLX5_FLOW_ACTION_COUNTER_OFFSET
enum and with a kernel driver includes
MLX5_IB_ATTR_CREATE_FLOW_ARR_COUNTERS_DEVX_OFFSET enum.

When the PMD uses rdma-core API to assign a batch counter to a root
table flow using invalid counter offset, it should get an error only
if the batch counter assignment for root table is supported.
Using this trial in the initialization time can help to detect the
support.

Using the above trial, if the support is valid, remove the management of
single counter container in the fast counter mechanism. Otherwise, move
the counter mechanism to fallback mode.

Signed-off-by: Suanming Mou <suanmingm@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>