fix service port allocator same port number different protocol issue

[adohe-zz]

Try to fix #20092
@thockin ptal.

[k8s-bot]

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[adohe-zz]

Close this as it will not fix the original issue.

[thockin]

This alone is insufficient, but we might get away without storing two maps by simply saying

• the port map is unified across protocols
• if a service has 2 ports that use the same port number but different protocols, allocate the first nodePort and use the same value for the 2nd port

This will prevent the case of ports being used in one protocol but not the other and failing to allocate.

Something like:

ServicePortToNodePort := map[int][int]{}
for i, sp := svc.Spec.Ports {
    np := ServicePortToNodePort[sp.Port]
    if np == 0 {
        np = allocateUnusedNodePort()
        ServicePortToNodePort[sp.Port] = np
    }
    sp.NodePort = np
}

I haven;t tried too hard to break it, but something like that MIGHT work.