net/mlx5: LAG and SRIOV cannot be used together

Until support will be added for RoCE LAG SRIOV.

Signed-off-by: Aviv Heller <avivh@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>