Rollup merge of #107764 - maurer:llvm-16, r=cuviper

llvm-16: Use Triple.h from new header location.

LLVM 16 has moved Triple.h from ADT and into TargetParser.

LLVM [landed a commit](https://github.com/llvm/llvm-project/commit/62c7f035b4392c1933550eead6ddab35122720bc) this morning moving the header. This change should make rustc continue to build against LLVM main.