[llvm] llvm: Add missing `LLVM_ABI` annotations (PR #171629)

[Nikita Popov via llvm-commits]

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@@ -25,11 +25,12 @@ enum class KCFIHashAlgorithm { xxHash64, FNV1a };
 KCFIHashAlgorithm parseKCFIHashAlgorithm(StringRef Name);
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nikic wrote:

Why only the two below and not this one?

https://github.com/llvm/llvm-project/pull/171629