* change cudnn helper for auto-tune

* Add FLAGS_use_autotune to set the global status of autotune and change the order of choosing algorithm.

* Fix the bug in calculating and printing current step cache hit rate.

* Improve the autotune cache and fix unittest.

* Change the key from AlgorithmType to int64_t.

* Fix unittest for cpu-only env.

* change ChooseAlgoByWorkspace for heuristic mode
Co-authored-by: NLiu Yiqun <liuyiqun01@baidu.com>

* Using the maximum workspace_size of all alogirhms to limit the workspace size in exhaustive search mode.

* Use the system cudaMalloc and cudaFree to allocate workspace during searching.

* Enable switch of two kind of workspace setting methods.
Co-authored-by: NLiu Yiqun <liuyiqun01@baidu.com>

* switch autotune

* implement AutoTuneCache

* implement AutoTuneCache class

* add pybind api

* add dygraph test

* support static mode and eager mode and improve unittests

* rename the SwitchAutoTune Class and improve tests

* improve AutoTuneStatus and reduce the cost of tests

* for 1st time interface combine.

* modification with kernel factory

* first auto_tune version.

* first version.

* basic version

* add warm up step.

* a debug version.

* optimize the functionality of class auto_tuner.

* add some quotes for optimized auto_tuner class.

* add some quotes for optimized auto_tuner class.

* add namespace.

* modification according to the advices

* replace fluid header with phi header.

* replace fluid header with phi header.

* add kernel profiler

* add gpu timer tool

* remove warmup

* fix rocm complilation error