Fix static IP issue for Azure internal LB

[karataliu]

What this PR does / why we need it:
Fix regression for Azure internal LB with static IP support

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #56686

Special notes for your reviewer:

Release note:

[k8s-ci-robot]

@karataliu: Adding do-not-merge/release-note-label-needed because the release note process has not been followed.

One of the following labels is required "release-note", "release-note-action-required", or "release-note-none".
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[andyzhangx]

/ok-to-test

[andyzhangx]

/lgtm
cc @jdumars
This works in v1.9.0-beta.0, but fails in v1.9.0-beta.1 . Could you mark it as v1.9 milestone? Thanks.

[andyzhangx]

/assign @brendandburns

[karataliu]

@brendandburns could you please take a look?

[k8s-github-robot]

[MILESTONENOTIFIER] Milestone Pull Request Current

@andyzhangx @brendandburns @karataliu

Note: This pull request is marked as priority/critical-urgent, and must be updated every 1 day during code freeze.

Example update:

ACK.  In progress
ETA: DD/MM/YYYY
Risks: Complicated fix required

Pull Request Labels

• sig/azure: Pull Request will be escalated to these SIGs if needed.
• priority/critical-urgent: Never automatically move pull request out of a release milestone; continually escalate to contributor and SIG through all available channels.
• kind/bug: Fixes a bug discovered during the current release.

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[dims]

@colemickens @jdumars - please approve if appropriate

[brendandburns]

/approve

[k8s-github-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: andyzhangx, brendandburns, karataliu

Associated issue: 56686

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Needs approval from an approver in each of these OWNERS Files:

• pkg/cloudprovider/providers/azure/OWNERS [brendandburns]

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[k8s-github-robot]

/test all [submit-queue is verifying that this PR is safe to merge]

[k8s-github-robot]

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions here.