Commit f326cbba breaks mx31pdk,
as the _end section in u-boot.lds is missing for the nand_spl
production.

Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>