FIXME removal: ignore SDLK_WORLD keys when not translating keyboard l…

…ayout.

This is a lesser-used codepath that probably doesn't need this feature,
which we probably can't supply in any reasonable way anyhow.

Reference Issue #143.

src/SDL12_compat.c

@@ -4093,7 +4093,6 @@ Scancode20toKeysym12(const SDL_Scancode scancode20)
     default: break;
     }
 
-    FIXME("map some of the SDLK12_WORLD keys");
     return SDLK12_UNKNOWN;
 }