DFSG of disk image with contrib package

[Emmanuel Kasper <manu@debian.org>]

Hi
I am building debian disk images for the Vagrant tool, distributed at
https://app.vagrantup.com/debian/

For extended functionality, I build some of the disk images with a
package from contrib, namely virtualbox-dkms

Due to having this virtualbox-dkms from contrib, the disk images are
labelled "contrib" in the distribution channel.

Now virtualbox-dkms is in contrib, because the compiler (openwatcom),
needed to compile a *different* part of the virtualbox source package,
the BIOS, is not DFSG.

Am I right in keeping these disk image as "contrib", or I am
overcomplicating by keeping these multiple disk image builds ?

Cc involved debian-cloud people and virtualbox maintainer

Don't beat to hard, it is my first post on -devel :)

Manu