Fixing bug in knob prunign script

llvm/projects/hpvm-tensor-rt/autotuner/tuner_driver_src/knob_pruning.py

@@ -48,7 +48,7 @@ def getPrunedKnobs(binary_path, layer_file, global_knobs_file, \
           createPromiseFile(l_knob, layer_ind, num_layers)
           accuracy = runBinary(binary_path)
           acc_loss = baseline_acc - accuracy
-          if acc_loss > acc_slack:
+          if acc_loss <= acc_slack:
               pruned_layer_knobs.append(l_knob)
 
       pruned_knobs.append(pruned_layer_knobs)
@@ -57,7 +57,8 @@ def getPrunedKnobs(binary_path, layer_file, global_knobs_file, \
       
   
   print ("*** knobs = ", knobs)
-    
+
+  return pruned_knobs