update build infrastructure for llvm-16.0.6
Update build infrastructure for LLVM 13.0.0.
Update clang build infrastructure for LLVM 11.1.0.Heavy lifting by mortimer@, thank you so much!
Update build infrastructure for LLVM 10.0.0.ok hackroom@tested by plenty
Update clang build infrastructure for LLVM 8.0.0.
Add infrastructure to compile and link LLDB. Inspecting core filesworks, but actually running stuff probably won't.ok kettenis@