[clang] [clang] Add support for Debian 14 Forky and Debian 15 Duke (PR #138460)

[Martin Storsjö via cfe-commits]

mstorsjo wrote:

> Seems like the cherry-pick only works if the branch of the PR still exists. 🤔

That's not my experience with it. It looks like the cherry-pick command yesterday just hit an unrelated issue: https://github.com/llvm/llvm-project/actions/runs/14837157160/job/41650945562

https://github.com/llvm/llvm-project/pull/138460