[libc++] Implement P1328R1 constexpr std::type_info::operator==

Differential Revision: https://reviews.llvm.org/D143447

NOKEYCHECK=True
GitOrigin-RevId: 16a1c851713a5825daed8ea4a887078a63488562
diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index 8a04afb..20b2b09 100644
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -38,6 +38,8 @@
 Implemented Papers
 ------------------
 
+- P1328R1 - `constexpr type_info::operator==()`
+
 Improvements and New Features
 -----------------------------