[clang] [clang][DebugInfo] Attach `DISubprogram` to additional call variants (PR #166202)

[J. Ryan Stinnett via cfe-commits]

jryans wrote:

I have attempted to carry over the points made so far into https://github.com/llvm/llvm-project/issues/168851. Let's try to focus further discussion there.

https://github.com/llvm/llvm-project/pull/166202