add instance norm kernel and ut

* set arm_lang default is off. test=develop

* fix resize error, test-develop

* add lookup_dequant_op

* feat: add opencl elementwise_sub op & ut

* enhance gather, lookup_table arm kernel uts

* enhance beam_search, beam_search_decoder, increment rigster

[LITE][OPENCL][Image] revert router of depthwisespl --> fix mnasnet and nanoyolo ,test=develop (#3109)

* [CORE] Support Clang compiling for Android
test=develop

* fix lto for jni so
test=develop

* disable assembly code
test=develop

* disable layout.cc
test=develop

* refine
test=develop

* Enable LTO on Clang
test=develop

* Disable LTO when clang is used.
test=develop

* Remove space
test=develop

* [Core] enable clang in build.sh
test=develop

* [Core] Remove the workaround for clang compiling
test=develop

* add lrn op

* fix v7 build error, test=develop

* [LITE][CMAKE] support clang compile for armv8 cpu. test=develop

* add build for clang. test=develop

* fix cmake format. test=develop

* [Lite][OpenCL]fix depthwise_conv3*3 test. test=develop

* [Lite][OpenCL]fix depthwise_conv3*3 test, format codestyle. test=develop

* get the precision from the real tensor or tensor_array of base_scope in arena/framwork

* register assign and assign_value to kAny

* fix

* fix format. test=develop

* fix format, test=develop

* fix resize error

* fix format. test=develop

* fix format, test=develop

* fix format

* note log(4) << x_image. test=develop

* note x_image printf. test=develop

* [MLU] support resnet50 on MLU

* [MLU] support resnet50 on MLU

* [LITE][DOC] Enhance OpenCL Doc. test=develop, test=document_fix

* fix opencl doc. test=develop, test=document_fix

* add note in source compile. test=develop, test=document_fix

* fix: fix nlp ops input and output type
* fix: add elementwise x_dims>y_dims case

* Fix act bug for opencl kernel. test=develop

* add print ActToStr. test=develop

* remove print code. test=develop

* Fix memory_resuse for opencl. test=develop

* remove useless code. test=develop

* test=develop

* test=develop

add opencl kernel build list; set num cores to build opencl in ci_build.sh and build.sh. test=develop (#3081)

* scale support int32 input

* test=devellop

* add cl file into resulted lib test=develop

* test=develop

* test=develop

* add grid sampler

* reset act

* fix conflict and readme, test=develop

* fix ios v8 run error

* fix grid_sampler compute error. test=develop

* fix exp act run error, test=develop

* fix format, test=develop