On current implementation, we may re-run ntp configuration even it
already configured.
Also, the system may configured with non-default ntp client, we just
ignoring that and configure with default ntp client.
This patch minimize unnecessary re-configuration of ntp client.
It run in following order:
1. Check NTP client is already running. If it running, skip setup
2. Check NTP client is alrady installed. If it installed, use it
3. If there is non of NTP client package installed,
- if it's CentOS, install chrony
- if it's on other distributions, install systemd-timesyncd
Related with #8344, #8339
735c83b27f