[llvm] [llvm-objcopy] Add --compress-sections (PR #85036)

[Fangrui Song via llvm-commits]

MaskRay wrote:

> This should have a release note.
> 
> Looks like most of my test comments haven't been addressed?

Sorry, I did not notice them. Addresses all, I think. https://github.com/llvm/llvm-project/issues/87027 is about `DebugCompressionType` renaming

https://github.com/llvm/llvm-project/pull/85036