[U-Boot] tools: board config CONFIG_SYS_BOOTM_LEN is being ignored

[Philipp Puschmann]

Hi,

i noticed that CONFIG_SYS_BOOTM_LEN, set in board config, and used in common/bootm.c is ignored
when compiling the tools like mkimage and fit_check_sign. The default 8MB is used and fit_check_sign
may fail with "Loading Kernel Image ... Image too large: increase CONFIG_SYS_BOOTM_LEN". Still the U-Boot
binary built with the increased CONFIG_SYS_BOOTM_LEN works without problem.

I'm unsure how and where to fix it. The Makefile system ist not quite easy to understand and the CONFIG_* options
are spread over various files during build time.

Regards,
Philipp