IB/mlx5: Expose correct maximum number of CQE capacity

Maximum number of EQE capacity per CQ was mistakenly exposed
as CQE. Fix that.

Fixes: 938fe83c ("net/mlx5_core: New device capabilities handling")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>