OMAP2420: hwmod data: Add McSPI

Update the omap2420 hwmod data with the McSPI info.
Add a device attribute structure which will be used
for passing number of chipselects from hwmod data.
Add revision macros to be passed from rev field from
hwmod.

Signed-off-by: Charulatha V <charu@ti.com>
Signed-off-by: Govindraj.R <govindraj.raja@ti.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>