pico-imx7d: Make SPL binary fit into 64kB

Currently SPL binary is larger than 64kB, which is larger than
CONFIG_SPL_MAX_SIZE defined in imx7_spl.h.

This causes boot failure on the pico-mx7 targets.

Remove CONFIG_SPL_LIBDISK_SUPPORT option for now, so that the SPL
binary can fit into the 64kB range.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
3 files changed