Modern DKMS no longer handles Debian package creation

[al177]

We have relied on DKMS's built-in mkdsc/mkdeb commands to generate Debian packages from a minimal description file. DKMS maintainers decided a couple of years ago that DKMS should remain distro-agnostic and removed distro specific package creation. Now the change has trickled down to RaspiOS and I can no longer generate packages for release.

The solution is to explicitly package the build product during build. Good thing it's a holiday weekend...