[clang] Fix preprocessed block comment newline on windows containing extra carriage return (PR #205084)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman commented:

Thank you for working on this! The changes should come with a test to ensure we don't regress behavior. It should also have a release note in `clang/docs/ReleaseNotes.rst` so users know about the fix.

https://github.com/llvm/llvm-project/pull/205084