ata: dwc_ahsata: Add ahci driver model support

Disable this support for cm_fx6 to avoid breakage.

Signed-off-by: Soeren Moch <smoch@web.de>
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 7ebee75..593e9cb 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -66,6 +66,14 @@
 	  Enable this driver to support the DWC AHSATA SATA controller found
 	  in i.MX5 and i.MX6 SoCs.
 
+config DWC_AHSATA_AHCI
+	bool "Enable DWC AHSATA AHCI driver support"
+	depends on DWC_AHSATA
+	depends on AHCI
+	default y
+	help
+	  Enable this option unless you need your private ahci implementation
+
 config FSL_SATA
 	bool "Enable Freescale SATA controller driver support"
 	select LIBATA