Adjustable ADC debounce delay (#16264)

Marlin/Configuration_adv.h

   //#define TFT_BTOKMENU_COLOR 0x145F // 00010 100010 11111 Cyan
 #endif
 
+//
+// ADC Button Debounce
+//
+#if HAS_ADC_BUTTONS
+  #define ADC_BUTTON_DEBOUNCE_DELAY 16  // (ms) Increase if buttons bounce or repeat too fast
+#endif
+
 // @section safety
 
 /**

Marlin/src/inc/SanityCheck.h

     #error "SHOW_REMAINING_TIME currently requires a Graphical LCD."
   #endif
 #endif
+
+#if HAS_ADC_BUTTONS && defined(ADC_BUTTON_DEBOUNCE_DELAY) && !WITHIN(ADC_BUTTON_DEBOUNCE_DELAY, 16, 255)
+  #error "ADC_BUTTON_DEBOUNCE_DELAY must be an integer from 16 to 255."
+#endif

Marlin/src/module/temperature.cpp

     #endif
 
     #if HAS_ADC_BUTTONS
+      #ifndef ADC_BUTTON_DEBOUNCE_DELAY
+        #define ADC_BUTTON_DEBOUNCE_DELAY 16
+      #endif
       case Prepare_ADC_KEY: HAL_START_ADC(ADC_KEYPAD_PIN); break;
       case Measure_ADC_KEY:
         if (!HAL_ADC_READY())
           next_sensor_state = adc_sensor_state; // redo this state
-        else if (ADCKey_count < 16) {
+        else if (ADCKey_count < ADC_BUTTON_DEBOUNCE_DELAY) {
           raw_ADCKey_value = HAL_READ_ADC();
           if (raw_ADCKey_value <= 900UL * HAL_ADC_RANGE / 1024UL) {
             NOMORE(current_ADCKey_raw, raw_ADCKey_value);
             }
           }
         }
-        if (ADCKey_count == 16) ADCKey_pressed = true;
+        if (ADCKey_count == ADC_BUTTON_DEBOUNCE_DELAY) ADCKey_pressed = true;
         break;
-    #endif // ADC_KEYPAD
+    #endif // HAS_ADC_BUTTONS
 
     case StartupDelay: break;