2a7abb04e2
This is the same diff I've put up at many times before. I've been trying to add some brand new functionality to the LLDB test infrastucture (create split-dwarf files!), and we all know that no good deed goes unpunished. The last attempt was reverted because it didn't work on the Fuchsia build. There are no code differences between this and [the](https://github.com/llvm/llvm-project/pull/90622) [previous](https://github.com/llvm/llvm-project/pull/87676) [four](https://github.com/llvm/llvm-project/pull/86812) [diffs](https://github.com/llvm/llvm-project/pull/85693) landed & reverted (due to testing infra failures). The only change in this one is the way `dwp` is being identified in `Makefile.rules`. Thanks to @petrhosek for helping me figure out how the fuchsia builders are configured. I now prefer to use llvm-dwp and fall back to gnu's dwp if the former isn't found. Hopefully this will work everywhere it needs to.