Convert Encoder callbacks to be boolean functions (#12805)

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

keyboards/rocketboard_16/keymaps/via/keymap.c

@@ -37,7 +37,7 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
  )
 };
 
-void encoder_update_user(uint8_t index, bool clockwise){
+bool encoder_update_user(uint8_t index, bool clockwise){
   if(index == 0) { // first encoder
     if(clockwise){
       tap_code(KC_AUDIO_VOL_UP);
@@ -51,6 +51,7 @@ void encoder_update_user(uint8_t index, bool clockwise){
       rgblight_decrease_val();
     }
   }
+    return true;
 }
 
 #ifdef OLED_DRIVER_ENABLE