Description of problem:
It would be a nice feature if we could create a bridge and then patch it to another bridge inside of os-net-config.

Version-Release number of selected component (if applicable):


Actual results:
We can create bridges in os-net-config, but we can't yet create patches between the bridges.

Expected results:
We should be able to patch between bridges.

Additional info:
This would be nice for the following use case:

A 3rd-party Neutron driver needs to create ports that are on br-ex, but not have them be cleaned up by the neutron-ovs-cleanup script. One way to do this is to create a second bridge, then patch between the two bridges. Since the ports are not on br-ex, the neutron script won't clean up those ports.