AMDGPU/R600: Cleanup DAGCombine

Move SDLoc initialization to comon place.
fall back to AMDGPU version in one place

Differential Revision: https://reviews.llvm.org/D23900

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280030 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed