net/mlx5: Fix RDMA TX steering prio

User added steering rules at RDMA_TX were being added to the first prio,
which is the counters prio.
Fix that so that they are correctly added to the BYPASS_PRIO instead.

Fixes: 24670b1a ("net/mlx5: Add support for RDMA TX steering")
Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>