CSV: add a newline before filesystem info

ampel-firmware/csv_writer.cpp

@@ -87,6 +87,7 @@ namespace csv_writer {
   void initialize(const char *sensorId) {
     snprintf(filename, sizeof(filename), "/%s.csv", sensorId);
 
+    Serial.println();
     Serial.print(F("Initializing FS..."));
     if (mountFS()) {
       Serial.println(F("done."));