IB/mlx5: Route MADs for dual port RoCE

Route performance query MADs to the correct mlx5_core_dev when using
dual port RoCE mode.

Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>