AMDGPU: Remove dead pattern

This is the unsafe conversion pattern, but not guarded by
an unsafe math check. It is also already done in LegalizeDAG.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292173 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed