tty: remove dtr/rts use from the driver open methods

These are handled by the tty_port core code which will raise and lower the
carrier correctly in tty_wait_until_ready
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/serial/cp210x.c

@@ -399,12 +399,6 @@ static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port,
 
 	/* Configure the termios structure */
 	cp210x_get_termios(tty, port);
-
-	/* Set the DTR and RTS pins low */
-	cp210x_tiocmset_port(tty ? (struct usb_serial_port *) tty->driver_data
-			: port,
-		NULL, TIOCM_DTR | TIOCM_RTS, 0);
-
 	return 0;
 }