IB/mlx5: Support per device q counters in switchdev mode

IB/mlx5: Support per device q counters in switchdev mode

When parent mlx5_core_dev is in switchdev mode, q_counters are not
applicable to multiple non uplink vports.
Hence, have make them limited to device level.

While at it, correct __mlx5_ib_qp_set_counter() and
__mlx5_ib_modify_qp() to use u16 set_id as defined by the device.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Link: https://lore.kernel.org/r/20190723073117.7175-3-leon@kernel.org
Signed-off-by: Doug Ledford <dledford@redhat.com>