Similar to T317175

See https://apps.juniper.net/feature-explorer/feature-info.html?fKey=8739&fn=System%20logging%20over%20management%20VRF%20(mgmt_junos)

MX routers now support sending syslog through mgmt_junos which seems more appropriate than the production interface.

Similarly for NTP, see https://www.juniper.net/documentation/us/en/software/junos/junos-getting-started/topics/topic-map/management-interface-in-non-default-instance.html

NTP would allow us to remove the loopback rules allow_ntp_src4/6 and allow_ntp_dst4/6

The mgmt firewalls ACLs might need to be updated accordingly.