added support for msys2 mingwtoolchains and fix x64 cocos/audio on windows platform for MSVC and Mingw. Also fixed a few very bad type casts very important for future Arm64 bit processors
fixed CCImage for MSVC someone added std:tolower which broke it
removed unneeded directories for Mingw cmake
Merge pull request #4434 from martell/msys2

Msys2 and Mingw added fixed x64 cocos/audio on Windows for MSVC and MinGW