[clang] [SystemZ][z/OS] This change adds support for the PPA2 section in zOS (PR #65407)

[Fangrui Song via cfe-commits]

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@@ -43,6 +43,7 @@ enum class Language : uint8_t {
   HLSL,
   ///@}
 };
+const char *LanguageToString(Language L);
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MaskRay wrote:

`languageToString`? This file correctly uses `functionName` unlike many other Clang files...

https://github.com/llvm/llvm-project/pull/65407