queue: do not impl Clone for QueueState

We should not implement Clone for QueueState, otherwise there may be
multiple actors operating on the same underlying queue.

Signed-off-by: Liu Jiang <gerry@linux.alibaba.com>

Author: jiangliu

crates/virtio-queue/src/state.rs

@@ -22,7 +22,7 @@ use crate::defs::{
 use crate::{error, AvailIter, Descriptor, Error, QueueStateGuard, QueueStateT, VirtqUsedElem};
 
 /// Struct to maintain information and manipulate state of a virtio queue.
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 pub struct QueueState {
     /// The maximum size in elements offered by the device.
     pub max_size: u16,