net/mlx5e: Add support for SR-IOV ndos

Implement and enable SR-IOV ndos to manage SR-IOV configuration via
netdev netlink API.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>