1. Proposed title of this feature request
Support NodeClockNotSynchronising when NTP service is disabled but OCP cluster is using PTP-Operator for time sync

2. What is the nature and description of the request?
Currently, when install an SNO OCP Telco Cluster and use the time sync refference from ptp-operator, alertmanager service is going to fire an alert continously entitled `NodeClockNotSynchronising` because the alerting rule its checking only if the NTP sync exists on the system as described in here.
3. Why does the customer need this? (List the business requirements here)
Since we are providing two time syncronization systems this should cover the use of both systems so the system is not firing false-positive alerts. In the above describe situation the systems are time sync using ptp-operator BUT the system is sending alerts for not beying synchronised.
4. List any affected packages or components.

• ptp-operator
• chronyc
• alertmanager