Fix allegro5 demo font path

demo/allegro5/main.c

@@ -120,7 +120,7 @@ int main(void)
     al_register_event_source(event_queue, al_get_mouse_event_source());
     al_register_event_source(event_queue, al_get_keyboard_event_source());
 
-    font = nk_allegro5_font_create_from_file("../../../extra_font/Roboto-Regular.ttf", 12, 0);
+    font = nk_allegro5_font_create_from_file("../../extra_font/Roboto-Regular.ttf", 12, 0);
 
     ctx = nk_allegro5_init(font, display, WINDOW_WIDTH, WINDOW_HEIGHT);