Fix CreateSeriesListIfNotExists() data race.
Fix CreateSeriesListIfNotExists() data race.

vladlopes/influxdb,vladlopes/influxdb,mark-rushakoff/influxdb,linearb/influxdb,runner-mei/influxdb,archsaber/influxdb,nooproblem/influxdb,benbjohnson/influxdb,influxdb/influxdb,nooproblem/influxdb,influxdb/influxdb,mark-rushakoff/influxdb,benbjohnson/influxdb,mark-rushakoff/influxdb,mark-rushakoff/influxdb,runner-mei/influxdb,benbjohnson/influxdb,influxdb/influxdb,vladlopes/influxdb,influxdb/influxdb,nooproblem/influxdb,archsaber/influxdb,influxdata/influxdb,vladlopes/influxdb,linearb/influxdb,chenziliang/influxdb,chenziliang/influxdb,benbjohnson/influxdb,nooproblem/influxdb,mark-rushakoff/influxdb,linearb/influxdb,archsaber/influxdb,influxdb/influxdb,chenziliang/influxdb,mark-rushakoff/influxdb,li-ang/influxdb,influxdb/influxdb,archsaber/influxdb,chenziliang/influxdb,linearb/influxdb,runner-mei/influxdb,influxdata/influxdb,runner-mei/influxdb,li-ang/influxdb,linearb/influxdb,nooproblem/influxdb