add release notes

Author: mariusdr

clang/docs/ReleaseNotes.rst

@@ -344,6 +344,8 @@ Bug Fixes in This Version
 - Defining an integer literal suffix (e.g., ``LL``) before including
   ``<stdint.h>`` in a freestanding build no longer causes invalid token pasting
   when using the ``INTn_C`` macros. (#GH85995)
+- Fixed an assertion failure in the expansion of builtin macros like ``__has_embed()`` with line breaks before the
+  closing paren. (#GH133574)
 
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^