[clang] Suppress octal literal diagnostics from system macros (PR #192481)

[via cfe-commits]

llvmbot wrote:

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Failed to cherry-pick: 027ca61e5cc040c4db1d6219a9843b81432d5ea6

https://github.com/llvm/llvm-project/actions/runs/24563837407

Please manually backport the fix and push it to your github fork.  Once this is done, please create a [pull request](https://github.com/llvm/llvm-project/compare)

https://github.com/llvm/llvm-project/pull/192481