Fix inference performance problem caused by selecting cudnn kernel of softmax (#47338)

* fix inference perfermence problem caused by selecting cudnn kernel for softmax

* recover use_cudnn in opmaker of softmax

paddle/fluid/operators/softmax_op.cc

@@ -83,6 +83,11 @@ class SoftmaxOpMaker : public framework::OpProtoAndCheckerMaker {
         "Defaults to \"NHWC\". Specify the data format of the output data, "
         "the input will be transformed automatically. ")
         .SetDefault("AnyLayout");
+    AddAttr<bool>(
+        "use_cudnn",
+        "(bool, default false) Only used in cudnn kernel, need install cudnn")
+        .SetDefault(false)
+        .AsExtra();
     AddComment(R"DOC(
 Softmax Operator.
 

paddle/phi/api/yaml/op_compat.yaml

@@ -686,7 +686,7 @@
 - op : softmax
   backward : softmax_grad
   extra :
-    attrs : [bool use_cudnn = false, bool use_mkldnn = false, str mkldnn_data_type = "float32", bool is_test = false]
+    attrs : [bool use_mkldnn = false, str mkldnn_data_type = "float32", bool is_test = false]
 
 - op : softplus
   backward : softplus_grad