trim firmware size

quantum/quantum.c

@@ -666,22 +666,25 @@ void matrix_init_quantum() {
 }
 
 void matrix_scan_quantum() {
+#if defined(AUDIO_ENABLE)
     // There are some tasks that need to be run a little bit
     // after keyboard startup, or else they will not work correctly
     // because of interaction with the USB device state, which
     // may still be in flux...
+    //
+    // At the moment the only feature that needs this is the
+    // startup song.
     static bool     delayed_tasks_run  = false;
     static uint16_t delayed_task_timer = 0;
     if (!delayed_tasks_run) {
         if (!delayed_task_timer) {
             delayed_task_timer = timer_read();
         } else if (timer_elapsed(delayed_task_timer) > 300) {
-#if defined(AUDIO_ENABLE)
             audio_startup();
-#endif
             delayed_tasks_run = true;
         }
     }
+#endif
 
 #if defined(AUDIO_ENABLE) && !defined(NO_MUSIC_MODE)
     matrix_scan_music();