[CRIU] [PATCH v3] Add CRIU support for amdgpu dmabuf

[David Francis]

This patch series adds support for CRIU checkpointing of processes that
share memory with the amdgpu dmabuf interface.

In this v3, the sockets used by CRIU to exchange dmabuf
fds between restoring processes have been refactored to be created within the
amdgpu plugin itself.

In the accompanying kernel patch set, the drm interfaces have been changed
from creating buffer objects with specified gem handles to changign the gem
handle of an existing buffer object.