[libcxx] [llvm] [libc++][C++03] Use `__cxx03/` headers in C++03 mode (PR #109002)

[Louis Dionne via llvm-commits]

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@@ -2240,6 +2245,7 @@ def version_header(self) -> str:
 #endif
 
 {feature_test_macros}
+#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
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ldionne wrote:

That is a stray `#endif`.

```suggestion

```

https://github.com/llvm/llvm-project/pull/109002