Zabbix

...G...... [ZBX-20448] improved error message when failed to accept incoming connection

Merge in ZBX/zabbix from feature/ZBX-20448-5.0 to release/5.0

* commit 'd984d5ce4c1daf3261df6626a60d46d585510844':
  .D........ [ZBX-20448] added ChangeLog entry
  ...G...... [ZBX-20448] improved error message when failed to accept incoming connection
  ...G...... [ZBX-20448] improved error message when failed to accept incoming connection
  ...G...... [ZBX-20448] fixed unhelpful log message for server listener in Zabbix agent 2