New event notifications and corresponding performance counters for openonu-adapter-go

To increase transparency towards the operator the following new event notifications and corresponding performance counters should be introduced in the core to enable openonu-adapter-go to address them :

• MIB data sync mismatch
• MIB resync mismatch
• malfunction of OMCI communication channel
  OMCI CRC issue counters (could not be a problem, OMCI has 3 repeat)
  OMCI packet counter to ensure that we get as many replies as we send
  OMCI packet error count is difference between sent and received.
• ONU restart initiated by adapter (HIGH PRIO)
  needed only in case the ONU gets rebooted (reboot event is needed)
  Very important because it’s service impacting
  connected to 1/2
• self initiated adapter restart (LOW PRIO)
  Unknown currently to DT Non existing in legacy system, You can get this from K8s events