[clang] Match against all plugins when parsing microsoft attributes (PR #86426)

[Erich Keane via cfe-commits]

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@@ -345,6 +345,9 @@ Bug Fixes to Compiler Builtins
 Bug Fixes to Attribute Support
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+- Clang now correctly matches plugin attributes with microsoft ``[attribute]`` syntax.
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erichkeane wrote:

> Microsoft attributes use single brackets, c++11 attributes use `[[]]`

Ah, woops!  I saw that later on and fixed it in my suggestion, but not the message above.  But please capitalize 'Microsoft' as suggested.

https://github.com/llvm/llvm-project/pull/86426