Use always-cpu policy for pipeline benchmark

hpvm/projects/visc-rt/visc-rt.cpp

@@ -74,7 +74,8 @@ void llvm_visc_policy_init() {
 //  policy = new NodePolicy();
 //  policy = new IterationPolicy();
 //  policy = new DeviceStatusPolicy();
-  policy = new InteractivePolicy();
+  // policy = new InteractivePolicy();
+  policy = new ConstPolicy(0);
   cout << "DONE: Initializing policy object.\n";
 }