Micron NAND flash (e.g. MT29F4G08ABADAH4) BLOCK LOCK READ STATUS is not
the same as others.  Instead of bit 1 being lock, it is #lock_tight.
To make the driver support either format, ignore bit 1 and use only
bit 0 and bit 2.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>