[clang] [SystemZ][z/OS] Implement #pragma export (PR #141671)

[Erich Keane via cfe-commits]

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@@ -918,6 +918,11 @@ WebAssembly Support
 AVR Support
 ^^^^^^^^^^^
 
+SystemZ Support
+^^^^^^^^^^^^^^^
+
+- Add support for `#pragma export` for z/OS
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erichkeane wrote:

We definitely need a much better intro/documentation here in the release notes.

https://github.com/llvm/llvm-project/pull/141671