A variable that lets you manually hint extra gamecontroller db entries.
Defined in SDL_hints.h
#define SDL_HINT_GAMECONTROLLERCONFIG "SDL_GAMECONTROLLERCONFIG"
The variable should be newline delimited rows of gamecontroller config data, see SDL_gamecontroller.h
This hint must be set before calling SDL_Init(SDL_INIT_GAMECONTROLLER) You can update mappings after the system is initialized with SDL_GameControllerMappingForGUID() and SDL_GameControllerAddMapping()