serial: core: Remove cast from void ptr in uart_open()

void * promotes to any pointer type; remove type cast.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/serial_core.c

@@ -1580,7 +1580,7 @@ static void uart_dtr_rts(struct tty_port *port, int onoff)
  */
 static int uart_open(struct tty_struct *tty, struct file *filp)
 {
-	struct uart_driver *drv = (struct uart_driver *)tty->driver->driver_state;
+	struct uart_driver *drv = tty->driver->driver_state;
 	int retval, line = tty->index;
 	struct uart_state *state = drv->state + line;
 	struct tty_port *port = &state->port;