Creality DWIN simple beeper

Marlin/src/pins/stm32f1/pins_CREALITY_V4.h

   #define BTN_EN2                           PB12
 
   //#define LCD_LED_PIN                     PB2
-  #define BEEPER_PIN                        PB13
+  #ifndef BEEPER_PIN
+    #define BEEPER_PIN                      PB13
+    #undef SPEAKER
+  #endif
 
 #elif ENABLED(DWIN_VET6_CREALITY_LCD)