Instead of the bash script, use binman to generate the FIT for arm64.
For 32-bit boards, use binman for all images, dropping the intermediate
files.
With this change, only Zynq is now using SPL_FIT_GENERATOR so update the
Kconfig rule accordingly.
Clean up the Makefile to the extent possible. Unfortunately, two boards
do not use SPL_FRAMEWORK so don't enable the u-boot.img rule:
evb-rk3036
kylin-rk3036
So a small remnant remains.
Signed-off-by: Simon Glass <sjg@chromium.org>
31f35e83b1