net/queue: export qemu_net_queue_append_iov

This will be used by buffer filter implementation later to
queue packets.

Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
diff --git a/net/queue.c b/net/queue.c
index 16dddf0..de8b9d3 100644
--- a/net/queue.c
+++ b/net/queue.c
@@ -112,12 +112,12 @@
     QTAILQ_INSERT_TAIL(&queue->packets, packet, entry);
 }
 
-static void qemu_net_queue_append_iov(NetQueue *queue,
-                                      NetClientState *sender,
-                                      unsigned flags,
-                                      const struct iovec *iov,
-                                      int iovcnt,
-                                      NetPacketSent *sent_cb)
+void qemu_net_queue_append_iov(NetQueue *queue,
+                               NetClientState *sender,
+                               unsigned flags,
+                               const struct iovec *iov,
+                               int iovcnt,
+                               NetPacketSent *sent_cb)
 {
     NetPacket *packet;
     size_t max_len = 0;