[clang] [clang][Tooling] Fix assertion failure when processing CUDA files (PR #173762)

[Aaron Ballman via cfe-commits]

AaronBallman wrote:

Thanks @jhuber6! Based on that, I think the only things missing here are a test case so we don't regress behavior and a release note in `clang/docs/ReleaseNotes.rst` so users know about the fix.

https://github.com/llvm/llvm-project/pull/173762