mmc: sh_mobile_sdhi: pass card hotplug GPIO number to TMIO MMC

To use TMIO MMC driver ability to interface to the generic MMC GPIO card
hotplug detection helper, the SDHI driver has to pass the GPIO number
from its own platform data.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>