docs: def _add_fcp(self, fcp):
          """add fcp to db if it's not in db but in fcp list and init it"""
          try:
              LOG.info("fcp %s found in CONF.volume.fcp_list, add it to db" %
                       fcp)
              self.db.new(fcp)
          except Exception:
              LOG.info("failed to add fcp %s into db", fcp)