aio: rename AIOPool to AIOCBInfo

Now that AIOPool no longer keeps a freelist, it isn't really a "pool"
anymore.  Rename it to AIOCBInfo and make it const since it no longer
needs to be modified.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/thread-pool.c b/thread-pool.c
index 651b324..204f70b 100644
--- a/thread-pool.c
+++ b/thread-pool.c
@@ -216,7 +216,7 @@
     qemu_mutex_unlock(&lock);
 }
 
-static AIOPool thread_pool_cb_pool = {
+static const AIOCBInfo thread_pool_aiocb_info = {
     .aiocb_size         = sizeof(ThreadPoolElement),
     .cancel             = thread_pool_cancel,
 };
@@ -226,7 +226,7 @@
 {
     ThreadPoolElement *req;
 
-    req = qemu_aio_get(&thread_pool_cb_pool, NULL, cb, opaque);
+    req = qemu_aio_get(&thread_pool_aiocb_info, NULL, cb, opaque);
     req->func = func;
     req->arg = arg;
     req->state = THREAD_QUEUED;