add to release notes

Signed-off-by: Sarnie, Nick <[email protected]>

Author: sarnex

clang/docs/ReleaseNotes.rst

@@ -840,6 +840,7 @@ Bug Fixes to AST Handling
 - Fixed type checking when a statement expression ends in an l-value of atomic type. (#GH106576)
 - Fixed uninitialized use check in a lambda within CXXOperatorCallExpr. (#GH129198)
 - Fixed a malformed printout of ``CXXParenListInitExpr`` in certain contexts.
+- Fixed a malformed printout of certain calling convention function attributes. (#GH143160)
 
 Miscellaneous Bug Fixes
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