nand_spl_simple: store ecc data on the stack

nand_spl_simple: store ecc data on the stack

Currently nand_spl_simple puts it's temp data at 0x10000 offset in SDRAM
which is likely to contain already loaded data.
The patch saves the oob data and the ecc on the stack replacing
the fixed address in RAM.

Signed-off-by: Stefano Babic <[email protected]>
CC: Ilya Yanok <[email protected]>
CC: Scott Wood <[email protected]>
CC: Tom Rini <[email protected]>
CC: Simon Schwarz <[email protected]>
CC: Wolfgang Denk <[email protected]>
Signed-off-by: Scott Wood <[email protected]>