[CUDA][HIP][DebugInfo] Skip reference device function

Summary:
- A device functions could be used as a non-type template parameter in a
  global/host function template. However, we should not try to retrieve that
  device function and reference it in the host-side debug info as it's
  only valid at device side.

Subscribers: aprantl, jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58992

llvm-svn: 355551