Add the exposed SD card slots. The on-board eMMC needs to wait until we
fixed the 8bit support.
Signed-off-by: NAi Kyuse <ai.kyuse.uw@renesas.com>
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>