arm, imx, spi: detect spi flash again on aristainetos board

155fa9af95 "spi: mxc: fix sf probe when using mxc_spi" break
spi flash detection on the aristainetos board. Fix this.

Signed-off-by: Heiko Schocher <hs@denx.de>

board/aristainetos/aristainetos.c

@@ -230,6 +230,12 @@ static iomux_v3_cfg_t const backlight_pads[] = {
 	MX6_PAD_GPIO_2__GPIO1_IO02 | MUX_PAD_CTRL(NO_PAD_CTRL),
 };
 
+int board_spi_cs_gpio(unsigned bus, unsigned cs)
+{
+	return (bus == CONFIG_SF_DEFAULT_BUS && cs == CONFIG_SF_DEFAULT_CS)
+		? (IMX_GPIO_NR(3, 20)) : -1;
+}
+
 static void setup_spi(void)
 {
 	int i;

include/configs/aristainetos.h

@@ -77,7 +77,7 @@
 #define CONFIG_SPI_FLASH_STMICRO
 #define CONFIG_MXC_SPI
 #define CONFIG_SF_DEFAULT_BUS		3
-#define CONFIG_SF_DEFAULT_CS		(0|(IMX_GPIO_NR(3, 20)<<8))
+#define CONFIG_SF_DEFAULT_CS		0
 #define CONFIG_SF_DEFAULT_SPEED		20000000
 #define CONFIG_SF_DEFAULT_MODE		SPI_MODE_0
 #define CONFIG_SYS_SPI_ST_ENABLE_WP_PIN