fix virtio_gpu use-after-free while creating dumb

euleros inclusion
catagery: bugfix
bugzilla: 46917

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virtio_gpu drop reference from allocate in virtio_gpu_gem_create when creating
dumb, but after that, this process will continue to use virtio_gpu_object
in virtio_gpu_object_attach, which cause uaf. See defail in bugzilla.

Signed-off-by: chenmaodong <chenmaodong@huawei.com>
Reviewed-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Cheng Jian <cj.chengjian@huawei.com>