This reverts commit 84b3ae3ae9.
The logic was incorrect[1]. We cannot achieve QoS egress minimum bandwidth of Linuxbridge by the patch. I also think that the issue is not solved by small patch and we must consider deeply.
[1]: https://bugs.launchpad.net/neutron/+bug/1662582
Change-Id: Id4703b5c63876f16e31b6805cd147b5840a4a591