coroutine: remove qemu_co_queue_wait_insert_head

qemu_co_queue_wait_insert_head() is unused in qemu code base now.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

include/block/coroutine.h

@@ -120,12 +120,6 @@ void qemu_co_queue_init(CoQueue *queue);
  */
 void coroutine_fn qemu_co_queue_wait(CoQueue *queue);
 
-/**
- * Adds the current coroutine to the head of the CoQueue and transfers control to the
- * caller of the coroutine.
- */
-void coroutine_fn qemu_co_queue_wait_insert_head(CoQueue *queue);
-
 /**
  * Restarts the next coroutine in the CoQueue and removes it from the queue.
  *

qemu-coroutine-lock.c

@@ -41,14 +41,6 @@ void coroutine_fn qemu_co_queue_wait(CoQueue *queue)
     assert(qemu_in_coroutine());
 }
 
-void coroutine_fn qemu_co_queue_wait_insert_head(CoQueue *queue)
-{
-    Coroutine *self = qemu_coroutine_self();
-    QTAILQ_INSERT_HEAD(&queue->entries, self, co_queue_next);
-    qemu_coroutine_yield();
-    assert(qemu_in_coroutine());
-}
-
 /**
  * qemu_co_queue_run_restart:
  *