[MTD] [NAND] Bug on atmel_nand HW ECC : OOB info not correctly written

The functions that write the OOB info (on hardware ECC only) use the 
HW_SYNDROME method.

This is not correct : the start position is "pos = eccsize + chunk" and 
should be eccsize. So, the standard (nand_write_oob_std) function should 
be used. This patch corrects this by using NAND_ECC_HW instead of 
NAND_ECC_HW_SYNDROME.

This has only been tested on small pages nand flash.
(if anyone can test it on large pages that would be great).

kernel version : 2.6.27-rc2 (current git mtd-2.6)

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>