This adds vduse header to linux headers so that the
relevant VDUSE API can be used in subsequent patches.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20220523084611.91-5-xieyongji@bytedance.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>