nand_info is now an array of pointers, with the actual mtd_info
instance embedded in struct nand_chip.
This is in preparation for syncing the NAND code with Linux 4.6,
which makes the same change to struct nand_chip. It's in a separate
commit due to the large amount of changes required to accommodate the
change to nand_info.
Signed-off-by: Scott Wood <email@example.com>