The recently modified nand buswitth configuration is not aligned with
board reality: the double footprint on boards is always populated with 8bits
buswidth nand flashes.
So we have to consider that without particular configuration the 8bits
buswidth is selected by default.
Moreover, the previous logic was always using !board_have_nand_8bit(), we
change it to a simpler: board_have_nand_16bit().
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Tested-by: NLudovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

no board configure it as 'n' and it's an issue to merge all defconfigs
in one

On AT91SAM926x boards both types of NAND flash can be present
(8 and 16 bit data bus width).

so will pass it via system_rev
Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Cc: Patrice Vilchez <patrice.vilchez@atmel.com>