ids.cgi: Use the PID file to find suricata

The process changes it name to "Suricata-Main" which is why the previous
method did not work.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

html/cgi-bin/ids.cgi

@@ -1007,7 +1007,7 @@ sub show_mainpage() {
 
 	&Header::ServiceStatus({
 		$Lang::tr{'intrusion prevention system'} => {
-			"process" => "suricata",
+			"pidfile" => "/var/run/suricata.pid",
 		},
 	});