AMDGPU: Select DS insts without m0 initialization

GFX9 stopped using m0 for most DS instructions. Select
a different instruction without the use. I think this will
be less error prone than trying to manually maintain m0
uses as needed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319270 91177308-0d34-0410-b5e6-96231b3b80d8
31 files changed