USB: whiteheat: fix broken port configuration

When configuring the port (e.g. set_termios) the port minor number
rather than the port number was used in the request (and they only
coincide for minor number 0).

Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/whiteheat.c

@@ -649,7 +649,7 @@ static void firm_setup_port(struct tty_struct *tty)
 	struct whiteheat_port_settings port_settings;
 	unsigned int cflag = tty->termios.c_cflag;
 
-	port_settings.port = port->number + 1;
+	port_settings.port = port->number - port->serial->minor + 1;
 
 	/* get the byte size */
 	switch (cflag & CSIZE) {