Prereqs are not finding SDL.h for SDL_image

For SDL_image added 'SDL2' prereqs in  : https://github.com/PerlGameDev/Alien-SDL2/blob/experimental/inc/My/Utility.pm#L137

Still not working:

```
In file included from IMG.c:28:
SDL_image.h:27:17: error: SDL.h: No such file or directory
SDL_image.h:28:25: error: SDL_version.h: No such file or directory
SDL_image.h:29:24: error: begin_code.h: No such file or directory
``

```
