configs: AST2500 EVB: Enable SD controller

Enable the MMC subsystem and the Aspeed SD controller. Also enable the
use of the device tree for probing the controller.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
diff --git a/configs/evb-ast2500_defconfig b/configs/evb-ast2500_defconfig
index 59d41cb..b47ca5b 100644
--- a/configs/evb-ast2500_defconfig
+++ b/configs/evb-ast2500_defconfig
@@ -16,6 +16,7 @@
 CONFIG_CMD_I2C=y
 CONFIG_CMD_DHCP=y
 CONFIG_CMD_MII=y
+CONFIG_CMD_MMC=y
 CONFIG_CMD_PING=y
 CONFIG_DEFAULT_DEVICE_TREE="ast2500-evb"
 CONFIG_NET_RANDOM_ETHADDR=y
@@ -36,3 +37,10 @@
 CONFIG_SYSRESET=y
 CONFIG_TIMER=y
 CONFIG_WDT=y
+CONFIG_MMC=y
+CONFIG_DM_MMC=y
+CONFIG_MMC_SDHCI=y
+CONFIG_MMC_SDHCI_ASPEED=y
+CONFIG_MMC_VERBOSE=y
+CONFIG_OF_CONTROL=y
+CONFIG_OF_EMBED=y