sh: MSIOF/mmc_spi platform data for the Ecovec24 board

This patch adds MSIOF and mmc_spi platform data for
the CN11 port on the SuperH Ecovec24 board. No card
detect interrupt is available so the MMC code is
configured to poll. The WP signal is implemented
together with CD and power control. The board only
supports 3.3V power.

The platform data is wrapped in SDHI #ifdefs to
allow both the SDHI and the MSIOF to coexist. Only
one configuration is allowed at a time. The pin
routing is selected by a dip switch but we can
unfortunately not detect this setting at run time.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>