tty: USB does not need the filp argument in the drivers

And indeed none of them use it. Clean this up as it will make moving to a
standard open method rather easier.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index f5d0f64..1aa5d20 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -36,8 +36,7 @@
 #define DRIVER_DESC "USB HandSpring Visor / Palm OS driver"
 
 /* function prototypes for a handspring visor */
-static int  visor_open(struct tty_struct *tty, struct usb_serial_port *port,
-					struct file *filp);
+static int  visor_open(struct tty_struct *tty, struct usb_serial_port *port);
 static void visor_close(struct usb_serial_port *port);
 static int  visor_write(struct tty_struct *tty, struct usb_serial_port *port,
 					const unsigned char *buf, int count);
@@ -273,8 +272,7 @@
 /******************************************************************************
  * Handspring Visor specific driver functions
  ******************************************************************************/
-static int visor_open(struct tty_struct *tty, struct usb_serial_port *port,
-							struct file *filp)
+static int visor_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
 	struct usb_serial *serial = port->serial;
 	struct visor_private *priv = usb_get_serial_port_data(port);