[occm] Add node-address-type annotation to control LB member IP selection

[carterpewpew]

What this PR does / why we need it:

When nodes have multiple network interfaces, nodeAddressForLB always prefers InternalIP for load balancer pool members. If the user configures loadbalancer.openstack.org/member-subnet-id pointing to a subnet that corresponds to the node's ExternalIP, the pool members end up with an IP outside that subnet because the Octavia API lets the address field take precedence over subnet_id.

This PR adds a new service annotation loadbalancer.openstack.org/node-address-type that allows users to set ExternalIP to reverse the address selection priority. When set, ExternalIP is tried first with a fallback to InternalIP. Default behavior (InternalIP first) is unchanged.

Which issue this PR fixes(if applicable):
fixes #3090

Special notes for reviewers:

1. The annotation accepts the string ExternalIP (matching corev1.NodeExternalIP). Any other value (including empty/absent) preserves existing behavior.
2. getSubnetIDForLB intentionally passes "" for the new parameter since it auto-detects the subnet and should always use InternalIP for that purpose.
3. The applyNodeSecurityGroupIDForLB caller is also updated so the security group is applied to the port matching the address actually used for the pool member.

Release note:

[openstack-cloud-controller-manager] Add `loadbalancer.openstack.org/node-address-type` annotation to control which node address type (InternalIP or ExternalIP) is used for load balancer pool members.

[k8s-ci-robot]

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Hi @carterpewpew. Thanks for your PR.

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