Remove duplicate entry

Author: jaapmarcus

func/main.sh

@@ -962,7 +962,6 @@ is_format_valid() {
                 host)           is_object_format_valid "$arg" "$arg_name" ;;
                 hour)           is_cron_format_valid "$arg" $arg_name ;;
                 id)             is_int_format_valid "$arg" 'id' ;;
-                interface)      is_interface_format_valid "$arg" ;;
                 iface)          is_interface_format_valid "$arg" ;;
                 ip)             is_ip_format_valid "$arg" ;;
                 ip_name)        is_domain_format_valid "$arg" 'IP name';;