[libcxx] [llvm] [libc++] Deprecate and remove meaningless `<cxxx>` headers (PR #111615)

[A. Jiang via llvm-commits]

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@@ -43,7 +43,7 @@
 "","","","","",""
 "`P0032R3 <https://wg21.link/P0032R3>`__","Homogeneous interface for variant, any and optional","2016-06 (Oulu)","|Complete|","4.0",""
 "`P0040R3 <https://wg21.link/P0040R3>`__","Extending memory management tools","2016-06 (Oulu)","|Complete|","4.0",""
-"`P0063R3 <https://wg21.link/P0063R3>`__","C++17 should refer to C11 instead of C99","2016-06 (Oulu)","|Complete|","7.0",""
+"`P0063R3 <https://wg21.link/P0063R3>`__","C++17 should refer to C11 instead of C99","2016-06 (Oulu)","|Complete|","7.0","``<ccomplex>``, ``<cstdalign>``, ``<cstdbool>``, and ``<ctgmath>`` are deprecated since LLVM 20."
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frederick-vs-ja wrote:

Reverted.

https://github.com/llvm/llvm-project/pull/111615