net: 9p: virtio: drop owner assignment

virtio core already sets the .owner, so driver does not need to.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Message-Id: <20240331-module-owner-virtio-v2-18-98f04bfaf46a@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>