Add NLB loadbalancer private ipv4 addresses annotation similar to the elastic allocation ids annotation

[luckyganesh]

What would you like to be added:
For an NLB in AWS, for subnet mapping I should be able to add a private ips from the subnets that I'm mapping to
https://kubernetes-sigs.github.io/aws-load-balancer-controller/latest/guide/service/annotations/#private-ipv4-addresses

Why is this needed:
When using in production like environments, whenever we are deploying we want use static ips for the nlb so that it's reliable incase even if the loadbalancer is recreated. This feature is already present in the aws-loadbalancer-controller.

/kind feature

[k8s-ci-robot]

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