Grazie per la risposta ho sistemato mettendo userfile nel form ora mi restituisce questo;
Warning: move_uploaded_file(./var/www/html/controllo-accessi-rfid-tastierino-4x4.jpg): failed to open stream: No such file or directory in /var/www/html/arduino/Setting/Upload.php on line 20
Warning: move_uploaded_file(): Unable to move '/tmp/phprUL3oE' to './var/www/html/controllo-accessi-rfid-tastierino-4x4.jpg' in /var/www/html/arduino/Setting/Upload.php on line 20
Upload NON valido!