[ARM] pxa/em-x270: explicitly set .gpio_cs in TDO35S SPI chip data

After commit a7bb3909 ("spi: pxa2xx_spi:
introduce chipselect GPIO to simplify the common cases") the .gpio_cs
field in pxa2xx_spi_chip has to be set explicitly.
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Eric Miao <eric.miao@marvell.com>

arch/arm/mach-pxa/em-x270.c

@@ -646,6 +646,7 @@ static struct pxa2xx_spi_master em_x270_spi_info = {
 static struct pxa2xx_spi_chip em_x270_tdo24m_chip = {
 	.rx_threshold	= 1,
 	.tx_threshold	= 1,
+	.gpio_cs	= -1,
 };
 
 static struct tdo24m_platform_data em_x270_tdo24m_pdata = {