[clang] [clang-format] Set C11 instead of C17 for LK_C (PR #134472)

[via cfe-commits]

llvmbot wrote:

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Failed to cherry-pick: d71ee7d23048ca64d14a7536927a006867cea39a

https://github.com/llvm/llvm-project/actions/runs/14285590977

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/134472