/usr/src/linux-source-4.4.0/debian.master/control.d/vars.generic is in linux-source-4.4.0 4.4.0-130.156.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | arch="i386 amd64 armhf arm64 ppc64el s390x"
supported="Generic"
target="Geared toward desktop and server systems."
desc="=HUMAN= SMP"
bootloader="grub-pc [i386 amd64 x32] | grub-efi-amd64 [amd64 x32] | grub-efi-ia32 [i386 amd64 x32] | grub [i386 amd64 x32] | lilo [i386 amd64 x32] | flash-kernel [armhf arm64] | grub-ieee1275 [ppc64el]"
provides="kvm-api-4, redhat-cluster-modules, ivtv-modules, virtualbox-guest-modules [i386 amd64 x32]"
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