LLVM 23.x support

[rpereira-dev]

This probably prematured given that LLVM 23.x isn't released yet.

I had compilation issues due to LLVM 23.x breaking changes on two APIs:

• OptimizationLevel::Os and OptimizationLevel::Oz will be removed in 23.x
• .setObjectLinkingLayerCreator prototype will change

I have attached the patch I made to compile on my system: proteus-llvm-23.x.patch

[ggeorgakoudis]

Thank you @rpereira-dev! We may call upon you, or pick up your patches, once we add support for LLVM 23. I'll leave this issue open.