[llvm] [X86] With large code model, put functions into .ltext with large section flag (PR #73037)

[Arthur Eubanks via llvm-commits]

aeubanks wrote:

still need to resolve the conversation in https://github.com/llvm/llvm-project/pull/70358, just putting up codegen side of this

https://github.com/llvm/llvm-project/pull/73037