OpenstackCluster multi-az controlplane nodes

[spnngl]

/kind bug

What steps did you take and what happened:
[A clear and concise description of what the bug is.]

Created a cluster on a 3AZ openstack provider, hoped for controlplane nodes to be evenly distributed among them but it is not the case. I have most of the time 2az used and sometime just 1, we need to use 3 of them 100% of the time.

What did you expect to happen:

Controlplane nodes evenly distributed on all AZs explicited in OpenstackCluster.spec.controlPlaneAvailabilityZones

Anything else you would like to add:
[Miscellaneous information that will assist in solving the issue.]

Environment:

• Cluster API Provider OpenStack version (Or git rev-parse HEAD if manually built): v0.12.2
• Cluster-API version: v1.9.6
• OpenStack version: 3.14 (ovhcloud)
• Minikube/KIND version:
• Kubernetes version (use kubectl version): 1.32.2
• OS (e.g. from /etc/os-release): talos 1.9.2