mtd: add the support to parse out the full-id nand type

When we meet a full-id nand type whose @id_len is not zero, we can use
the find_full_id_nand() to parse out the necessary information for a
nand chip.

If we meet a non full-id nand type, we can handle it in the legacy way.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Reviewed-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>