Comment 8 for bug 1808595

A bug was introduced in [1], as seen in [2]. Error log:

neutronclient.common.exceptions.InvalidIpForNetworkClient: IP address 240.10.143.255 is not a valid IP for any of the subnets on the specified network.

Broadcast address can't be used. The initial position defined in [3] should be reduced by one, to avoid getting the broadcast address in the previously created IPSet.

[1] https://review.opendev.org/#/c/684279/
[2] https://8e5339063fd8d98f3aba-875157a44fab70cabf10b03c4d83bfb0.ssl.cf2.rackcdn.com/660722/22/check/neutron-fullstack/6ea7ccc/testr_results.html.gz
[3] https://github.com/openstack/neutron/blob/0fa7e74ebb386b178d36ae684ff04f03bdd6cb0d/neutron/tests/fullstack/base.py#L140