Zabbix proxy poller\unreachable poller crash in zbx_tls_close

1. PSK encryption is used in Zabbix agent<->proxy communication
2. There are autoregistration actions defined, but PSK for autoregstration isn't allowd\defined
3. Delete host from web UI (that has manually configured PSK)

the problem does not appear on every removed host, but on a regular basis. The more hosts are removed, the more likely you are to catch the problem