* [OPENCL][API] add opencl valid api for device. test=develop (#3951)

* move train demo code, test=develop

* test=develop

fix the demo of opt saved can't work on windows

 fix the doc

* test=develop, test=document_fix, the document of python demo

* test=develop, test=document_fix, the document of python compiled
Co-authored-by: Nhuzhiqiang <912790387@qq.com>

* test=develop, fix the x86 demo can't work on windows

* test=develop,test=document_fix, add the doc of python demo

* test=develop, add the document of windows compiled

* test=develop, modify the x86 demo on windows

* test=develop, modify the name of windows batch file

* test=develop, fix the doc

* [DOC] Enhance opencl docs for releasev2.6.0. (#3569)

test=develop, test=document_fix
Co-authored-by: NYuan Shuai <ysh329@users.noreply.github.com>

Remove the full publish from MTK APU doc

Modify cxx&python demo of Cuda backend 

* Fix OpenCL kernel of exp, tanh,

* Fix layout pass for opencl backend,

* Add how to debug cl kernel. test=develop.

add cuda c++ doc