To be used by the mlx5 Eth driver in following commit.

This is in preparation for netdev "light-weight" open/stop flow
change described in previous commit.
Signed-off-by: NAchiad Shochat <achiad@mellanox.com>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>