imx6ul secure the fcb with bch 40. The imx-kobs tool use a own modified
bch lib. They reverse the bit order of the data and the ecc.
To use the bch lib in barebox the bytes in the data buffers must be
reversed.
The data layout on nand is bit aligned. But with 40 bits this is not an
issue for imx6ul now.

Signed-off-by: Jan Remmet <J.Remmet@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>