Switch CMake (including the Core and GPU compile features and the Android
flag), the Visual Studio projects (stdcpp20), the legacy Android NDK
makefiles, the libretro makefiles and .ycm_extra_conf.py from C++17 to
C++20.
[=] lambdas that use this implicitly become [=, this], to avoid
-Wdeprecated-this-capture.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>