IB/mlx5: Expose RAW QP device handles to user space

Expose RAW QP device handles to user space by extending the UHW part of
mlx5_ib_create_qp_resp.

This data is returned only when DEVX context is used where it may be
applicable.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>