imx6: wandboard: fix dwc_ahsata build errors when DM enabled

Enable CONFIG_AHCI to fix errors:
drivers/ata/dwc_ahsata.c: In function `ahci_init_one':
drivers/ata/dwc_ahsata.c:868:21: error: `struct blk_desc' has no member named `priv'
sata_dev_desc[pdev].priv = uc_priv;
     ^
drivers/ata/dwc_ahsata.c: In function `init_sata':
drivers/ata/dwc_ahsata.c:891:30: error: `struct blk_desc' has no member named `priv'
uc_priv = sata_dev_desc[dev].priv;
...

Also enable DM_SCSI to fix migration build warning.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
diff --git a/configs/wandboard_defconfig b/configs/wandboard_defconfig
index 7f64ea6..ba0c844 100644
--- a/configs/wandboard_defconfig
+++ b/configs/wandboard_defconfig
@@ -10,6 +10,7 @@
 CONFIG_SPL=y
 CONFIG_SPL_LIBDISK_SUPPORT=y
 CONFIG_CMD_HDMIDETECT=y
+CONFIG_AHCI=y
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_NR_DRAM_BANKS=1
 CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=arch/arm/mach-imx/spl_sd.cfg"
@@ -52,9 +53,9 @@
 CONFIG_PINCTRL_IMX6=y
 CONFIG_DM_PMIC=y
 CONFIG_DM_PMIC_PFUZE100=y
+CONFIG_DM_SCSI=y
 CONFIG_DM_THERMAL=y
 CONFIG_USB=y
 CONFIG_DM_USB=y
 CONFIG_DM_VIDEO=y
 CONFIG_VIDEO_IPUV3=y
-# CONFIG_VIDEO_SW_CURSOR is not set