fixed ping response if fetching the status page return a error status code

[mprenditore]

Hi guys, I noted that when apache is stopped, the first time that zapache is called return a "ZBX_NOTSUPPORTED" even on ping, but the second time that is invoked it returns correctly "0". The "ZBX_NOTSUPPORTED" generate a delay in Zabbix, so the trigger will fire too late, so i fixed adding a special case inside the control of the return status code of the fetching function.