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

[Orlando Cazalet-Hyams via cfe-commits]

https://github.com/OCHyams commented:

SGTM, thanks for this, I think it looks right. Just a couple questions (one inline) -

Does `-g[no-]omit-unreferenced-methods` still work as expected?

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