ARM: uniphier: enable UniPhier SD/MMC host driver

Enable the driver in all UniPhier defconfig files and add some
needed defines to the common files.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/include/configs/uniphier.h b/include/configs/uniphier.h
index fcec0c0..9d14155 100644
--- a/include/configs/uniphier.h
+++ b/include/configs/uniphier.h
@@ -146,6 +146,10 @@
 #define CONFIG_FAT_WRITE
 #define CONFIG_DOS_PARTITION
 
+/* SD/MMC */
+#define CONFIG_CMD_MMC
+#define CONFIG_GENERIC_MMC
+
 /* memtest works on */
 #define CONFIG_SYS_MEMTEST_START	CONFIG_SYS_SDRAM_BASE
 #define CONFIG_SYS_MEMTEST_END		(CONFIG_SYS_SDRAM_BASE + 0x01000000)