ARM: mach-shmobile: armadillo800eva: add SDHI0 support

On armadillo800eva board,
CD (= Card Detect) pin is not connected to SDHI0_CD.
Then, we can use IRQ31 as card detect irq,
but it needs chattering removal operation.
We should use IRQ card detect in the future,
but this patch use polling mode at this point.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Simon Horman <horms@verge.net.au>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>