Convert Encoder callbacks to be boolean functions (#12805)

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

keyboards/delikeeb/waaffle/keymaps/default/keymap.c

@@ -104,7 +104,7 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
     return true;
 }
 
-void encoder_update_user(uint8_t index, bool clockwise) {
+bool encoder_update_user(uint8_t index, bool clockwise) {
     /* With an if statement we can check which encoder was turned. */
     if (index == 0) { /* First encoder */
         /* And with another if statement we can check the direction. */
@@ -145,4 +145,5 @@ void encoder_update_user(uint8_t index, bool clockwise) {
             }
         }
     }
+    return true;
 }