Look into possible implementation of the parent epic of this spike.

-Do we have all the required pieces in the OVN/OVS?
-Do we already have the implementation upstream, or partial implementaion for this upstream? E.g. https://bugs.launchpad.net/neutron/+bug/1865889
-What needs to happen in the downstream OPS 18.0 to implement this?

Little bit more backround after looking over upstream patches.
"Routed provided networks" for ML2/OVS has been around for a long time.
"Routed provided networks" for ML2/OVN has been around since ussari/train release (https://bugs.launchpad.net/neutron/+bug/1865889)
"Multiple routed provider segments" for ML2/OVS have been around since antelope(2023.1) (https://bugs.launchpad.net/neutron/+bug/1956435, https://review.opendev.org/c/openstack/neutron-specs/+/823823)
"Multiple routed provider segments" for ML2/OVN does not exists. We will most likely need to get started from the core OVN layer