[llvm] [llvm-objcopy][COFF] Support --rename-section (PR #210573)

[Fangrui Song via llvm-commits]

MaskRay wrote:

The code is probably reasonable, but the tests need substantial rework, and the review cost of iterating on heavily generated code is more than we can take on here. I hope an experienced contributor can put up a replacement patch. Please don't take this as a judgment on you. Smaller, hand-written changes are very welcome.

https://github.com/llvm/llvm-project/pull/210573