vdpa/vp_vdpa: implement kick_vq_with_data callback

Implement the kick_vq_with_data vDPA callback.
On kick, we pass the next available data to the hardware by writing it in
the kick offset.

Signed-off-by: Yuxue Liu <yuxue.liu@jaguarmicro.com>
Message-Id: <20241203023743.1757-1-yuxue.liu@jaguarmicro.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>