virtio-input is simple enough that it doesn't need to xfer any state.
Still we have to wire up savevm manually, so the generic pci and virtio
are saved correctly.

Additionally we need to do some post-load processing to figure whenever
the guest uses the device or not, so we can give input routing hints to
the qemu input layer using qemu_input_handler_{activate,deactivate}.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1459859501-16965-1-git-send-email-kraxel@redhat.com