Dear Maintainer,

I recently decided to jump from kernel 6.1 to 6.12 via debian backports.
(-t bookworm-backports).
I needed to ensure I had /etc/dkms/framework.conf pointing to a sign_file
executable, as I have secureboot with a custom platform key. I had tested
6.12 fairly extensively and wanted to remove kernel 6.1 from disk.
/etc/dkms/framework.conf says use "$kernelver".
sign_file="/usr/lib/linux-kbuild-$kernelver/scripts/sign-file"

The value in framework's $kernelver includes platform. This results in an
error.
Sign command: /usr/lib/linux-kbuild-6.12.32+bpo-amd64/scripts/sign-file
Binary /usr/lib/linux-kbuild-6.12.32+bpo-amd64/scripts/sign-file not found,
modules won't be signed

Kbuild (linux-kbuild-6.12.32+bpo) installs in
/usr/lib/linux-kbuild-maj.min.point+bpo/
/usr/lib/linux-kbuild-6.12.32+bpo/

I would expect either $kernelver to align with the kbuild naming
convention, or the kbuild naming convention to be exposed in dkms
framework.conf to ensure that modules are signed by the appropriate script.