Update the counter interface for multiple ports. Some counter sets
always comes from the primary device.

Port specific counters should be accessed per mlx5_core_dev not always
through the IB master mdev.
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>