[llvm] [JITLink] Some cleanups to EHFrameSupport (PR #66707)

[via llvm-commits]

lhames wrote:

Making my concern explicit: This could cause us to reject well-formed objects that would have been accepted before. The existing error check for that doesn't seem burdensome in either readability or performance -- I think that should have been left it.

Sorry -- probably should have been clearer about that in the review.

https://github.com/llvm/llvm-project/pull/66707