[llvm] [ORC-RT] Initial check-in for a new, top-level ORC runtime project. (PR #113499)

[Lang Hames via llvm-commits]

lhames wrote:

A couple of initial questions:

1. How should the runtime inherit compile options (e.g. `-fno-exceptions` and `-fno-rtti`)? Should it inherit them at all, or should it have its own defaults that can be overridden just for this runtime?

2. How should include directories and installation of headers be managed? For now I've created an interface library with an install command, but that was largely cargo-culted from Stack Overflow. If there's a better way to do this please let me know! 

https://github.com/llvm/llvm-project/pull/113499