Wrong error message when removing interface from router.

[Mamatisa Nurmatov]

Release: Train (applicable to master as well)
1) Two subnets from different nets with same cidr(10.0.0.0/24): subnet1, subnet2
2) subnet1 is added to router
3) subnet1 has ports with floating IP assigned
4) User is trying to delete subnet2 interface from router

Actual error: interface for subnet2 cannot be deleted as it is required by floating ip
Expected error: router has no interface on subnet2

[Mamatisa Nurmatov (isabek)]

Fix: https://review.opendev.org/c/openstack/neutron/+/765129

[Rodolfo Alonso (rodolfo-alonso-hernandez)]

That's weird because, as you stated, if both subnets have the same cidr, we check that the FIP internal IP address belongs to subnet_cidr, but in this case both are the same.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 18.0.0.0rc1 release candidate.

[Rodolfo Alonso (rodolfo-alonso-hernandez)]

Fix merged and released: https://review.opendev.org/c/openstack/neutron/+/765129