[clang] [C2y] Add stdcountof.h (PR #140890)

[Erich Keane via cfe-commits]

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@@ -260,6 +260,7 @@ static bool isBuiltinHeaderName(StringRef FileName) {
            .Case("stdarg.h", true)
            .Case("stdatomic.h", true)
            .Case("stdbool.h", true)
+           .Case("stdcountof.h", true)
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erichkeane wrote:

These too!

https://github.com/llvm/llvm-project/pull/140890