[llvm] [LLVM-C] Add LLVMCreateTargetMachineWithABI (PR #68406)

[Sebastian Poeplau via llvm-commits]

sebastianpoeplau wrote:

Done, modeled after the pass builder interface: Users create and manipulate an opaque option structure, then pass it to the new function `LLVMCreateTargetMachineWithOptions`; the implementation of `LLVMCreateTargetMachine` uses the option structure.

https://github.com/llvm/llvm-project/pull/68406