* Move XPU mean and mean_grad to phi, test=kunlun

* Fix stream, test=kunlun

* Replace ENFORCE, test=kunlun

* move huber_loss xpu kernel to phi, test=kunlun

* fix, test=kunlun

* fix paddle_enforce, test=kunlun

* move layer_norm xpu kernel to phi, test=kunlun

* fix, test=kunlun

* move xpu kernel to phi

* delete fluid file

* fix compile

* add guard, test=kunlun

* xpu set constant

* fix xpu error, test=kunlun

* mv elementwise add to xpu , test=kunlun

* fix ci bugs, test=kunlun

* fix ci bugs , test=kunlun

* [XPU] migrate mul to phi;test=kunlun

* rm fluid mul xpu op;test=kunlun

* gather gather_grad gather_nd gaussian_random xpu to phi

* move matmul_v2 kernel of xpu from fluid to phi, test=kunlun

* fix complie bug, test=kunlun

* fix complie bug, test=kunlun

* fix complie bug, test=kunlun

* make full_like support double_max in dygraph

* fix bug

* xpu unittest grad compute supports more types, *test=kunlun

* add instance norm xpu, *test=kunlun

* add some fp16 op for kunlun resnet50 model
*test=kunlun

* tmp
*test=kunlun

* fix cpu lars_momentum bug & add xpu grad_add/log_softmax/log_softmax_grad
*test=kunlun

* minor
*test=kunlun

* 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

* chnage dispatch to visit

* resolve conflict

* rename scalar_array to int_array

* update cmake

* fix conflict

* remove useless log

* [PHI] Migrate where_index op

* [PHI] Fix where_index infermate

* [Phi] set where_index out data type

* remove SetAllocationForOutputTenosr

* add place param for copy kernel

* recover SetAllocationForOutputTenosr

* polish code

* fix empty_dev api bug

* remove reseting dtype and layout for output in executor

* fix merge bug

* [Phi] Add ClearHolder when re-alloc on new place in DeviceContext

* fix hostAlloc

* remove setting output allocation

* remove full_kernel_impl.h

* fix bug of xpu full_like
Co-authored-by: NAurelius84 <zhangliujie@baidu.com>

* remove SetAllocationForOutputTenosr

* add place param for copy kernel

* recover SetAllocationForOutputTenosr

* polish code

* fix empty_dev api bug

* test=allcases

* test=allcases

* fix bug

* recover empty

* recover modify

* remove fill_any_like kernel in fluid and fix data transform bug

* support scalar in infershpe

* recover infershape in fill_and_like

* change Vector to std::vector and provide MixVector class as a helper wrapper class

* solve the multi-gpu hang problem

* remove the duplicate template instantialize

* Copy vector to cpu

* add CopyToCPU

* xxx

* final version: fix the problem of all reduce

* remove mixvector dependence

* fix

* merge

* fix code

* fix by CI

* unify register macro

* rename declare macro

* fix infrt error

* 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