Function send_ndp_packet 

pub fn send_ndp_packet<BC, CC, S>(
    core_ctx: &mut CC,
    bindings_ctx: &mut BC,
    device_id: &CC::DeviceId,
    src_ip: Option<SpecifiedAddr<Ipv6Addr>>,
    dst_ip: SpecifiedAddr<Ipv6Addr>,
    body: S,
    message: NdpMessage,
) -> Result<(), IpSendFrameError<S>>
where
    CC: IpLayerHandler<Ipv6, BC>,
    S: Serializer + PartialSerializer,
    S::Buffer: BufferMut,

Sends an NDP packet from device_id with the provided parameters.