[clang] Support target names with dots in more utilities (PR #65812)

[James Henderson via cfe-commits]

jh7370 wrote:

I can merge it for you, but first I just want to confirm that all 4 commits in this PR are intended to be for the PR? If not, you'll need to rebase and force push.

There's no need for you to manually squash the fixups (although you might as well if you do end up rebasing). When I do the merge via the UI, it'll be using the Squash and merge button, which squashes everything into a single commit.

The final commit message will be the PR description. I found the description a little confusing at first, without reading the code and test, so it may be beneficial to add an example of the before and after behaviour to that description before I merge it. Please could you update the patch description accordingly.

https://github.com/llvm/llvm-project/pull/65812