Function devices::virtio::create_descriptor_chain

pub fn create_descriptor_chain(
    memory: &GuestMemory,
    descriptor_array_addr: GuestAddress,
    buffers_start_addr: GuestAddress,
    descriptors: Vec<(DescriptorType, u32)>,
    spaces_between_regions: u32
) -> Result<DescriptorChain>

Test utility function to create a descriptor chain in guest memory.