*: fix some varcheck lint warnings

[Willendless]

What problem does this PR solve?

Issue Number: #22979

What is changed and how it works?

What's Changed:

• Remove some unused global var
• Disable linter for some false positive cases

Check List

Tests

• Unit test

Release note

• No release note

[CLAassistant]

All committers have signed the CLA.

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[disksing]

Thanks! @Willendless

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[zimulala]

/LGTM

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[zimulala]

/merge

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This pull request has been accepted and is ready to merge.

Commit hash: 5e07939

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