AP_Notify: make explicit define for notify's NCP5623

libraries/AP_Notify/AP_Notify.cpp

@@ -295,7 +295,7 @@ void AP_Notify::add_backends(void)
             case Notify_LED_ToshibaLED_I2C_External:
                 ADD_BACKEND(new ToshibaLED_I2C(TOSHIBA_LED_I2C_BUS_EXTERNAL));
                 break;
-#if !HAL_MINIMIZE_FEATURES
+#if AP_NOTIFY_NCP5623_ENABLED
             case Notify_LED_NCP5623_I2C_External:
                 FOREACH_I2C_EXTERNAL(b) {
                     ADD_BACKEND(new NCP5623(b));