* complete abs, fmod and sin function in simplemath.h
* remove some unused variables in simplemath.cpp
* modify test-coverage.yml and add some functions to simplemath.cpp
* modify erf.cpp which included math.h
* include platform.h for NCNN_SIMPLEMATH definition
* move utility constants and functions in simplemath.h to simplemath.cpp
* guard simplemath functions with extern "C"
* add NCNN_EXPORT macro in simplemath.h
* include plateform.h and guard all declarations with NCNN_SIMPLEMATH
* clean unused code in test_unaryop.cpp
* guard #include <vector> with NCNN_SIMPLEMATH in benchncnn.cpp
* add 'static' to guard functions that not declarated in header file
* modify sin and cos with better implementation
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Co-authored-by: HonestDeng <HonestDeng@users.noreply.github.com>
* [build] add toolchain file w/o stdcxx dependency
* [build] link m and gcc lib explicitly
* [ncnn] complete simple stl impl
* [ncnn] adapt for ncnn simplestl
* [test] adapt for ncnn simplestl
* [ncnn] fix missing algorithm and list when simplestl disabled
* [ncnn] fix guard for operator new and delete
* [style] fix the code style
* [build] fix build failed on darwin and emscripten
* [ci] do not import cxx to avoid operator conflict
* [ncnn] add temporary partial_sort impl using bubble sort
heap sort should be used for better perf.
* [ncnn] add std greater and less function
* [ncnn] fix placement new operator overload
* [ncnn] add operator delete with size info
* [build] disable exception, rtti, example and tools when simplestl on
* [build] add toolchain for arm simplestl
* [build] add toolchain for aarch64 simplestl
* [ncnn] move initializer to constructor
* [ncnn] use deteiled type instead of auto
* [ncnn] use plain lib name in target_link_libraries
nihui