* move DeviceContextPool to phi

* add EmplaceExternalContextFunc

* update namespace

* update cmake

* fix bugs and create context_pool_impl.h

* replace platform::is_xxx_place

* fix bugs

* update generator

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix enforce usage

* Revert "fix enforce usage"

This reverts commit 5f521f08a69713cee506e64a00ec6d9fba709e27.

* fix bugs

* rm XPUDeviceContext and CustomDeviceContext

* fix bugs

* fix fix context init bug

* fix bugs after merge

* fix bugs

* fix name

* fix mutable_data

* update and fix bugs

* fix bugs

* update

* fix bugs

* fix name

* fix bugs

* merge

* fix bugs

* create context_pool in phi/backends

* create context_pool in phi/backends

* fix bugs

* fix xpu bugs

* fix rocm bugs

* fix bugs

* fix bugs

* fix bugs

* fix xpu bugs

* update

* update

* fix bugs

* fix bugs

* move sequence_padding to phi

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix buga

* fix bugs

* revert and update phi::XPUContext

* move variable_utils from phi_api_utils to fluid

* fix coment

* update include

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* fix bugs

* update

* update

* fix CI-Windows-OpenBLAS

* fix bugs

* fix bugs

* fix bugs

* update include

* move variable_utils to phi_utils

* fix namespace

* try sequence_padding

* fix cant use mutable_data

* fix mistake fluid_sequence_scale.hh/CMakeLists.t include

* fix namespace bug

* fix framework::ToAbsOffset not found

* fix codestyle

* perfect copy

* deal with conflict

* deal with conflict

* fix compile bugs

* fix unittest bugs

* change code format

* deal with conflict

* modify code by review

* fix ce bugs

* fix ce bugs

* add lo

* perfect code format

* deal with conflicts

* 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

* moving OP

* move forward

* move grad and infershape

* code format

* format code

* fix code

* fix code

* fix CMakerLists.txt

* fix comments

* Refine CMakeLists for rocm ci