Fixed default Preonic keymap's encoder hadnling (#5067)

The function had the wrong name & arguments. This commit fixes this.
This in turn should also close issue #4997

keyboards/preonic/keymaps/default/keymap.c

@@ -233,7 +233,7 @@ uint16_t muse_counter = 0;
 uint8_t muse_offset = 70;
 uint16_t muse_tempo = 50;
 
-void encoder_update(bool clockwise) {
+void encoder_update_user(uint8_t index, bool clockwise) {
   if (muse_mode) {
     if (IS_LAYER_ON(_RAISE)) {
       if (clockwise) {