raylib-d Gamepad Detection Fails

[jwatson-CO-edu]

On Friday, 2 December 2022 at 01:03:47 UTC, Steven Schveighoffer 
wrote:
> It's important to remember that raylib-d doesn't do any special 
> things with the raylib functions -- they are just straight 
> calls into the library.
>
> -Steve

Indeed, I plugged a different gamepad into the same system 
running the same code, and it worked.  My gamepad must not have 
been on the list of [gamepad input 
mappings](https://github.com/gabomdq/SDL_GameControllerDB/blob/master/gamecontrollerdb.txt) used by SDL2 --> GLFW --> Raylib --> raylib-d.