board: ge: bx50v3: make SATA optional and disabled by default

The SATA support is only useful for development and shouldn't be enabled
in production, so it has to be disabled in U-boot by default.

Signed-off-by: Andrew Shadura <andrew.shadura@collabora.co.uk>
diff --git a/include/configs/ge_bx50v3.h b/include/configs/ge_bx50v3.h
index ccaa2b4..98f20c6 100644
--- a/include/configs/ge_bx50v3.h
+++ b/include/configs/ge_bx50v3.h
@@ -60,13 +60,14 @@
 #define CONFIG_MXC_OCOTP
 
 /* SATA Configs */
-#define CONFIG_CMD_SATA
+#ifdef CONFIG_CMD_SATA
 #define CONFIG_DWC_AHSATA
 #define CONFIG_SYS_SATA_MAX_DEVICE	1
 #define CONFIG_DWC_AHSATA_PORT_ID	0
 #define CONFIG_DWC_AHSATA_BASE_ADDR	SATA_ARB_BASE_ADDR
 #define CONFIG_LBA48
 #define CONFIG_LIBATA
+#endif
 
 /* MMC Configs */
 #define CONFIG_FSL_ESDHC