After upgrading to poky pyro, generation of grub2 menuentry in grub2
became broken. Our init-install.sh script, origianlly coming from an old
poky version, was modified in poky
c2e63957d5abaa4bb10507da5ba16f01112d0bf5 to adapt to the fact that
/etc/grub.d/40_custom was not there anymore. We need to do the same,
otherwise the menyentry is not appended to the grub config and the
installed image won't boot correctly.
In modern Poky the facade is gone and the data dictionary needs
to be accessed directly. This commit is catching up with it. It
was build tested on dora as well. I have not checked if it is
changing the checksums of a dora build.