arm: rmobile: lager: Add support SDHI

Lager board has two SDHI port as SDHI0 and SDHI2.
This adds GPIO configuration and initialization function of SDHI, and
enables MMC command.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/configs/lager_defconfig b/configs/lager_defconfig
index 1602a9b..950b037 100644
--- a/configs/lager_defconfig
+++ b/configs/lager_defconfig
@@ -3,3 +3,4 @@
 CONFIG_TARGET_LAGER=y
 CONFIG_DM=y
 CONFIG_DM_SERIAL=y
+CONFIG_SH_SDHI=y