[clang] [clang] Avoid MS RTTI type_info name explosion (PR #206317)

[Eli Friedman via cfe-commits]

efriedma-quic wrote:

Please add a release note (clang/docs/ReleaseNotes.md).

Please set a public email address on GitHub (https://llvm.org/docs/DeveloperPolicy.html#email-addresses).

Please update the patch description (the first comment in the PR) to correspond to the new version, since that becomes the commit message in squash mode on GitHub.

I'm not sure the ‎clang/test/CodeGenCXX/mangle-ms-rtti-lambda.cpp is really useful at this point; it shows the issue with the first version of the patch, but that's not likely to break.

https://github.com/llvm/llvm-project/pull/206317