[clang] Redesign handling of anyAppleOS availability attribute (PR #190817)

[Allan Shortlidge via cfe-commits]

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@@ -988,20 +993,16 @@ void DiagnoseUnguardedAvailability::DiagnoseDeclAvailability(
     const char *ExtraIndentation = "    ";
     std::string FixItString;
     llvm::raw_string_ostream FixItOS(FixItString);
-    // If the attr was derived from anyAppleOS, emit the fix-it using
-    // anyAppleOS and the original anyAppleOS version rather than the
-    // platform-specific name and version.
-    VersionTuple OrigAnyAppleOSVersion = AA->getOrigAnyAppleOSVersion();
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tshortli wrote:

The `getOrigAnyAppleOSVersion()` declaration and its backing storage should be removed now, right?

https://github.com/llvm/llvm-project/pull/190817