[lld] [llvm] [X86][llvm][CodeGen] Use 64-bit EH encodings for medium code model (PR #174637)

[Peter Smith via llvm-commits]

https://github.com/smithp35 commented:

As an Arm employee I'm limited in what I can comment on for X86_64 specific changes. This is more a policy question for x86 maintainers.

On the lld side I've left a comment that I don't think the test is suitable for LLD.

https://github.com/llvm/llvm-project/pull/174637