Zabbix

........S. [ZBX-20490] fixed initial ha failover delay update, improved RTC and HA service communications and exit handling

Merge in ZBX/zabbix from feature/ZBX-20490-5.5 to master

* commit 'ad4f0689d225af98c4d17a091d7613b4156e46ea':
  .D........ [ZBX-20490] added changelog entry
  ........S. [ZBX-20490] fixed server cache reloading crashing after swithcing to standby and back to active mode
  ........S. [ZBX-20490] added explicit ha_ parameters to server_startup() to improve code readability
  ........S. [ZBX-20490] removed updating main process with ha status when starting ha manager
  ........S. [ZBX-20490] fixed handling of unresponsive HA manager at startup
  ........S. [ZBX-20490] reworked the ha_failover_delay handling by main process
  ........S. [ZBX-20490] reverted explicit update parent IPC message to ha manager
  .......PS. [ZBX-20490] removed redundant check
  .......PS. [ZBX-20490] fixed check if child exited
  ........S. [ZBX-20490] fixed check if child exited
  ........S. [ZBX-20490] added explicit update parent IPC message to ha manager
  ........S. [ZBX-20490] disable locks before stopping ha manager
  ........S. [ZBX-20490] fixed ha manager not being stopped if server is shutdown when it has no access to database
  .......PS. [ZBX-20490] fixed handling of runtime control option during initial configuration sync