[clang] [clang][NFC] Remove unused diagnostic (PR #181790)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Timm Baeder (tbaederr)

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<summary>Changes</summary>



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Full diff: https://github.com/llvm/llvm-project/pull/181790.diff


1 Files Affected:

- (modified) clang/include/clang/Basic/DiagnosticASTKinds.td (+2-4) 


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https://github.com/llvm/llvm-project/pull/181790