simple-shm: remove an unnecessary call of wl_display_get_fd()

Reviewed-by: Nils Chr. Brause <nilschrbrause@gmail.com>

clients/simple-shm.c

@@ -393,8 +393,6 @@ create_display(void)
 		exit(1);
 	}
 
-	wl_display_get_fd(display->display);
-	
 	return display;
 }