use new sorted queue with double link chain for quick push

src/sf_ordered_writer.c

@@ -223,7 +223,7 @@ static int sf_ordered_writer_init_thread(SFOrderedWriterContext *context,
     }
 
     if ((result=sorted_queue_init(&thread->queues.buffer, (unsigned long)
-                    (&((SFOrderedWriterBuffer *)NULL)->next),
+                    (&((SFOrderedWriterBuffer *)NULL)->dlink),
                     (int (*)(const void *, const void *))
                     compare_buffer_version)) != 0)
     {

src/sf_ordered_writer.h

@@ -29,7 +29,7 @@ typedef struct sf_writer_version_entry {
 typedef struct sf_ordered_writer_buffer {
     int64_t version;
     BufferInfo bf;
-    struct sf_ordered_writer_buffer *next;
+    struct fc_list_head dlink;
 } SFOrderedWriterBuffer;
 
 typedef struct sf_orderd_writer_thread {