cmd: move ELF load and boot to lib/elf.c

Loading and running the ELF image is the responsibility of the
library and should not be associated with the command line interface.

It is also required to run ELF images from FIT with the bootm command
so as not to depend on the command line interface.

Signed-off-by: Maxim Moskalets <maximmosk4@gmail.com>
3 files changed