[client] sdl: move SDL specific screensaver inhibit out of main.c

client/displayservers/SDL/sdl.c

@@ -36,6 +36,9 @@ static struct SDLDSState sdl;
 
 static bool sdlEarlyInit(void)
 {
+  // Allow screensavers for now: we will enable and disable as needed.
+  SDL_SetHint(SDL_HINT_VIDEO_ALLOW_SCREENSAVER, "1");
+
   return true;
 }