Don't depends on systemd for proxy-sqlite on el6

zabbix.spec

@@ -198,9 +198,16 @@ Zabbix proxy with PostgreSQL database support.
 Summary:		Zabbix proxy for SQLite3 database
 Group:			Applications/Internet
 Requires:		fping
+%if 0%{?rhel} >= 7
 Requires(post):		systemd
 Requires(preun):	systemd
 Requires(postun):	systemd
+%else
+Requires(post):         /sbin/chkconfig
+Requires(preun):        /sbin/chkconfig
+Requires(preun):        /sbin/service
+Requires(postun):       /sbin/service
+%endif
 Provides:		zabbix-proxy = %{version}-%{release}
 Provides:		zabbix-proxy-implementation = %{version}-%{release}
 Obsoletes:		zabbix