mtd: nand: omap: Copy platform data parameters to omap_nand_info data

Copy all the platform data parameters to the driver's local data
structure 'omap_nand_info' and use it in the entire driver. This will
make it easer for device tree migration.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>