* refactor the optional tensor

* remove optiona<MetaTensor> in InferMeta

* fix bug

* fix optional<vector<Tensor>>

* fix bug

* fix rmsprop

* fix amp of eager_gen

* polish code

* fix deleted code

* fix merge conflict

* polish code

* remove is_nullopt_

* fix merge conflict

* fix merge conflict

* unify utils naming style

* polish details

* split phi and fluid infermeta context

* resolve conflict

* fix type error

* optimize scheduling perf

* spec small vector size

* replace all grad var name

* fix test failed

* move init defalut signature

* polish details

* polish details

* fix no init bug

* init sig for tests

* add init sig for infer

* fix infrt error

* fix infrt failed

* fix kunlun error

* fix infrt failed

* remove flatten infermeta

* fix bugs when run inference ci

* fix bugs when run inference ci

* fix bugs when run ci

* support infrt

* inplace infershape code'

* replace prefix pt by pd

* replace added kernel

* revert util change

* pd kernel to phi

* resolve conflict

* resolve conflict

* rename pten dir to phi

* rename namespace to phi

* rename infrt pten dir to phi

* resolve conflict

* rename pten to phi in cmake

* revert all infrt change

* change needed files

* fix infrt failed

* fix inference failed

* infermeta context init design

* support infermeta called in fluid op

* add hasattr and attr methods

* add dygraah GetVarPtrs support

* rename arg_map_context to arg_map_utils

* add registry for arg map func

* resolve conflit

* refactor op utils design

* polish meta config

* fix details

* remove hasattr method

* resolve conflit

* revert cmake order change

* revert some change

* change init pos

* fix compile faileed

* fix typo

* fix inference failed

* fix windows ccompile failed

* polish format
Co-authored-by: NWang Huan <wanghuan29@baidu.com>