USB: serial: keyspan_pda: remove unused variable

Remove an unused variable which was mistakingly left by commit
37faf50 ("USB: serial: keyspan_pda: fix write-wakeup
use-after-free") and only removed by a later change.

This is needed to suppress a W=1 warning about the unused variable in
the stable trees that the build bots triggers.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/keyspan_pda.c

@@ -555,10 +555,8 @@ static int keyspan_pda_write(struct tty_struct *tty,
 static void keyspan_pda_write_bulk_callback(struct urb *urb)
 {
 	struct usb_serial_port *port = urb->context;
-	struct keyspan_pda_private *priv;
 
 	set_bit(0, &port->write_urbs_free);
-	priv = usb_get_serial_port_data(port);
 
 	/* queue up a wakeup at scheduler time */
 	usb_serial_port_softint(port);