Add nand lock / unlock routines. At least 'micron' parts
support this.
Signed-off-by: NVimal Singh <vimalsingh@ti.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>