The argument is superfluous because only run/image/uboot evaluated it
anyway, and the argument is always boot/image.elf. With this change, the
official semantics of run_image become: "replace the boot/image.elf file
by platform-specific file(s) at boot/ that can actually be booted".
Issue #4730
Both modules were quite similar except the the name of the FIT image
(image.itb) and the mkimage command line. FIT images are now produced by
the following RUN_OPT.
RUN_OPT += --include image/uboot --image-uboot-fit
Issue #4693
By making the use of gzip's '--best' option configurable and disabling it
by default, this patch noticably reduces the built-test cycle from 15 to
10 seconds when integrating the Sculpt system image for the PinePhone.
Fixes#4693
