Fix ARM intrinsics-overflow.ll test on Windows

Windows on ARM only supports thumb mode execution, so we have to
explicitly pick some non-Windows OS to test ARM mode codegen.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208448 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed