Do not duplicate grub.cfg in efiboot.img

Instruct the embeded grub.cfg to search for a volume with a
`/.disk/%UUID_SEARCH_FILENAME%.uuid` file and load `/EFI/BOOT/grub.cfg`
from it.

This avoid duplicating GRUB configuration files in two places (ISO 9660
and FAT) and ensures there is no confusion about which is the _correct_
configuration file.

Since nothing besides EFI binaries is copied to `efibootimg`, the
`_make_common_bootmode_grub_copy_to_efibootimg` function is removed.

Fixes #208

1 files changed, 2 insertions, 0 deletions

diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index d55c15d..e00ebcb 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -20,6 +20,8 @@ Changed
 - Identify the ISO volume via a UUID instead of a file system label to avoid collisions of multiple ISOs created in the
   same month.
 - Honor ``SOURCE_DATE_EPOCH`` in the ``date`` command used by ``profiledef.sh`` of the shipped profiles.
+- Do not duplicate ``grub.cfg`` in both ISO 9660 and the EFI system partition / El Torito image. GRUB will search for
+  the ISO volume and load the ``grub.cfg`` from there.
 
 Removed
 -------