Fix unit testint in test_prelu_op.

python/paddle/v2/framework/tests/test_prelu_op.py

@@ -17,10 +17,10 @@ class PReluTest(OpTest):
         assert out_np is not self.inputs['X']
         self.outputs = {'Out': out_np}
 
-    def not_test_check_output(self):
+    def test_check_output(self):
         self.check_output()
 
-    def not_test_check_grad(self):
+    def test_check_grad(self):
         self.check_grad(['X'], 'Out')