davinci: da8xx: add spi resources and registration routine

Add IO resource structures, platform data, and a registration
routine in order to support spi device on DA850/OMAP-L138/AM18x
and DA830/OMAP-L137/AM17x platforms.

Signed-off-by: Michael Williamson <michael.williamson@criticallink.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>