Apply TERN to compact code (#17619)

Marlin/src/HAL/shared/servo.cpp

@@ -150,9 +150,7 @@ void Servo::move(const int value) {
   if (attach(0) >= 0) {
     write(value);
     safe_delay(servo_delay[servoIndex]);
-    #if ENABLED(DEACTIVATE_SERVOS_AFTER_MOVE)
-      detach();
-    #endif
+    TERN_(DEACTIVATE_SERVOS_AFTER_MOVE, detach());
   }
 }