drivers: tty: imx: use setup_timer() helper.

    Use setup_timer function instead of initializing timer with the
    function and data fields.

Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>