name pin according to schematic

Change-Id: I94a7f2216c288150b044a6190804f9b7247eb10c
diff --git a/sysmoOCTSIM/main.c b/sysmoOCTSIM/main.c
index dfe3b03..f2584d2 100644
--- a/sysmoOCTSIM/main.c
+++ b/sysmoOCTSIM/main.c
@@ -30,7 +30,7 @@
 static void rx_cb_UART_debug(const struct usart_async_descriptor *const io_descr)
 {
 	/* Receive completed */
-	gpio_toggle_pin_level(LED_system);
+	gpio_toggle_pin_level(USER_LED);
 	data_arrived = true;
 }