RDMA/mlx5: Assign profile before calling stages

Assign the profile to the IB device before executing stages. This will
allow to check which profile is being used from within a stage.

Link: https://lore.kernel.org/r/20200506071602.7177-2-leon@kernel.org


Signed-off-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>