Revert "Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself.""""

After a successful build it seems to have come back on a later build.

This reverts commit r213391.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213432 91177308-0d34-0410-b5e6-96231b3b80d8