Revert "Reapply debug info changes now that r224385 has been recommitted to clang (in r224941)"

Asserting when building compiler-rt when using a gcc host compiler.
Reverting while I investigate.

This reverts commit r224942.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@224969 91177308-0d34-0410-b5e6-96231b3b80d8