RDMA/mlx5: Add vport metadata matching for IB representors

If vport metadata matching is enabled in eswitch, the rule created
must be changed to match on the metadata, instead of source port.

Signed-off-by: Jianbo Liu <jianbol@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>