RDMA/mlx5: Fix stack out-of-bounds read in cc_params debugfs

Cc: linux-rdma@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
To: Leon Romanovsky <leon@kernel.org>
To: Jason Gunthorpe <jgg@ziepe.ca>
To: Daniel Jurgens <danielj@mellanox.com>
To: Doug Ledford <dledford@redhat.com>
To: Parav Pandit <parav@mellanox.com>
To: Eli Cohen <eli@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

--- b4-submit-tracking ---
# This section is used internally by b4 prep for tracking purposes.
{
  "series": {
    "revision": 1,
    "change-id": "20260726-get-param-leaks-kernel-stack-memory-6b8c813fe849",
    "prefixes": [
      "rdma-next"
    ],
    "presubject": ""
  }
}