fix(agent): don't set Hostname when HostnameItem is set

Author: DocMarten

zabbix/files/default/etc/zabbix/zabbix_agentd.conf.jinja

@@ -189,9 +189,9 @@ ServerActive={{ settings.get('serveractive', defaults.serveractive) }}
 # Mandatory: no
 # Default:
 # Hostname=
-
+{% if not settings.get('hostnameitem', defaults.get('hostnameitem', False)) %}
 Hostname={{ settings.get('hostname', defaults.get('hostname', salt['grains.get']('id'))) }}
-
+{% endif %}
 ### Option: HostnameItem
 #	Item used for generating Hostname if it is undefined. Ignored if Hostname is defined.
 #	Does not support UserParameters or aliases.