mmc: mediatek: Add Mediatek MMC driver

Add Mediatek MMC driver code
Support eMMC/SD/SDIO

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index d5e107b..fd9a58e 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -776,3 +776,11 @@
 	tristate "Toshiba Type A SD/MMC Card Interface Driver"
 	depends on PCI
 	help
+
+config MMC_MTK
+	tristate "MediaTek SD/MMC Card Interface support"
+	help
+	  This selects the MediaTek(R) Secure digital and Multimedia card Interface.
+	  If you have a machine with a integrated SD/MMC card reader, say Y or M here.
+	  This is needed if support for any SD/SDIO/MMC devices is required.
+	  If unsure, say N.