serial:ifx6x60:Keep word size accordance with SPI controller

As protocol driver, IFX SPI driver initiate to setup SPI master with default
SPI word size as 16 bit/word, however, SPI master may not adopt this default
value due to SPI controller's capability, it might choose an available value by
itself and set it to spi_device.bits_per_word. In order to keep align with
Controller, IFX driver should make use of this value during SPI transfer,
but the default one.
Signed-off-by: Chen Jun <jun.d.chen@intel.com>
Signed-off-by: channing <chao.bi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/ifx6x60.c

@@ -811,7 +811,8 @@ static void ifx_spi_io(unsigned long data)
 		ifx_dev->spi_xfer.cs_change = 0;
 		ifx_dev->spi_xfer.speed_hz = ifx_dev->spi_dev->max_speed_hz;
 		/* ifx_dev->spi_xfer.speed_hz = 390625; */
-		ifx_dev->spi_xfer.bits_per_word = spi_bpw;
+		ifx_dev->spi_xfer.bits_per_word =
+			ifx_dev->spi_dev->bits_per_word;
 
 		ifx_dev->spi_xfer.tx_buf = ifx_dev->tx_buffer;
 		ifx_dev->spi_xfer.rx_buf = ifx_dev->rx_buffer;