Eduardo Gonzalez 483f32edb6 Fix mongodb name in cron.json
There is a typo in cron.json making cron to fail
when mongodb is enabled.
Only affect master.

```MissingRequiredSource:
/var/lib/kolla/config_files/logrotate/mongdb.conf file is not found```

Change-Id: I79d41e94ee3361f2b4d831d17b1bb34a1964f580
2017-06-06 12:11:22 +01:00
..
2017-06-06 12:11:22 +01:00