zabbix_agentd: Update to 6.0.16 (LTS)

zabbix_agentd: Update to 6.0.16 (LTS)

- Update from version 6.0.6 to 6.0.16
- Update of rootfile not required
- Changelog
 No substantial changes for Agent Linux version
 Changelogs since 6.0.6:
 - https://www.zabbix.com/rn/rn6.0.7
 - https://www.zabbix.com/rn/rn6.0.8
 - https://www.zabbix.com/rn/rn6.0.9
 - https://www.zabbix.com/rn/rn6.0.10
 - https://www.zabbix.com/rn/rn6.0.11
 - https://www.zabbix.com/rn/rn6.0.12
 - https://www.zabbix.com/rn/rn6.0.13
 - https://www.zabbix.com/rn/rn6.0.14
 - https://www.zabbix.com/rn/rn6.0.15
 - https://www.zabbix.com/rn/rn6.0.16

Signed-off-by: Robin Roevens <robin.roevens@disroot.org>