Clarify /etc/default/influxdb in logging instructions
Clarify /etc/default/influxdb in logging instructions

influxdata/docs.influxdata.com,influxdata/docs.influxdata.com,influxdata/docs.influxdata.com,influxdb/docs.influxdata.com,influxdata/docs.influxdata.com,influxdb/docs.influxdata.com,influxdb/docs.influxdata.com,influxdata/docs.influxdata.com