mtd: rawnand: use bit-wise majority to recover the ONFI param page

Per ONFI specification (Rev. 4.0), if all parameter pages have invalid
CRC values, the bit-wise majority may be used to recover the contents
of the parameter page from the parameter page copies present.

Signed-off-by: Jane Wan <Jane.Wan@nokia.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>