IB/mlx5: Fix leaking stack memory to userspace

mlx5_ib_create_qp_resp was never initialized and only the first 4 bytes
were written.

Fixes: 41d902cb7c32 ("RDMA/mlx5: Fix definition of mlx5_ib_create_qp_resp")
Cc: <stable@vger.kernel.org>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
static void set_reg_umr_seg(struct mlx5_wqe_umr_ctrl_seg *umr,
			    struct mlx5_ib_mr *mr, bool umr_inline)
{
	int size = mr->ndescs * mr->desc_size;

	memset(umr, 0, sizeof(*umr));

	umr->flags = MLX5_UMR_CHECK_NOT_FREE;
	if (umr_inline)
		umr->flags |= MLX5_UMR_INLINE;
	umr->xlt_octowords = cpu_to_be16(get_xlt_octo(size));
	umr->mkey_mask = frwr_mkey_mask();
}

static void set_reg_umr_seg(struct mlx5_wqe_umr_ctrl_seg *umr,
			    struct mlx5_ib_mr *mr, bool umr_inline)
{
	int size = mr->ndescs * mr->desc_size;

	memset(umr, 0, sizeof(*umr));

	umr->flags = MLX5_UMR_CHECK_NOT_FREE;
	if (umr_inline)
		umr->flags |= MLX5_UMR_INLINE;
	umr->xlt_octowords = cpu_to_be16(get_xlt_octo(size));
	umr->mkey_mask = frwr_mkey_mask();
}
