Cleanup VSOCK before spawning, feat request

[yooouuri]

let process = FirecrackerProcessBuilder::new("/usr/local/bin/firecracker", "/tmp/firecracker.sock")
    .id("firecracker")
    .no_seccomp(true)
    .cleanup_socket(true)
    .spawn()
    .await
    .unwrap();

process.vm_builder()
    .boot_source(BootSource {
        kernel_image_path: "/Users/youri/vmlinux".into(),
        boot_args: Some("console=ttyS0 reboot=k panic=1 pci=off init=/sbin/firecracker-init".into()),
        initrd_path: None,
    })
    .drive(Drive {
        drive_id: "rootfs".into(),
        path_on_host: Some("/Users/youri/rootfs.ext4".into()),
        is_root_device: true,
        is_read_only: Some(false),
        cache_type: DriveCacheType::Unsafe,
        io_engine: DriveIoEngine::Sync,
        partuuid: None,
        rate_limiter: None,
        socket: None,
    })
    .machine_config(MachineConfiguration {
        vcpu_count: std::num::NonZeroU64::new(2).unwrap(),
        mem_size_mib: 256,
        smt: false,
        track_dirty_pages: false,
        cpu_template: None,
        huge_pages: None,
    })
    .vsock(Vsock {
        vsock_id: None,
        guest_cid: 1,
        uds_path: DEFAULT_UDS_PATH.into(),
    })
    .start()
    .await
    .unwrap();

Is working fine, the firecracker socket is cleaned before spawning. Problem is the vsock isn't.