[llvm] [llvm-cov] Add --debug-info flag to llvm-cov to lookup debug info file. (PR #66798)

[Zequan Wu via llvm-commits]

ZequanWu wrote:

Maybe we can extend it further, make profile counter/data sections also strippable, because eventually we need to lookup `__llvm_covfun` and `__llvm_covmap` in the unstripped binary using llvm-cov for coverage results. And let llvm-cov construct the in-memory indexed profile from those 3 sections in the unstripped binary, and then creates coverage results. 
That would be a different mode, not under debug info correlation.

https://github.com/llvm/llvm-project/pull/66798