[MINOR] stats: make stats_dump_raw_to_buffer() use buffer_feed_chunk

Same as previous change. A remaining call to stats_dump_proxy()
still prevents us from completing the update.
diff --git a/include/proto/dumpstats.h b/include/proto/dumpstats.h
index 990c620..0ba3ae0 100644
--- a/include/proto/dumpstats.h
+++ b/include/proto/dumpstats.h
@@ -46,8 +46,7 @@
 
 int stats_sock_parse_request(struct stream_interface *si, char *line);
 void stats_io_handler(struct stream_interface *si);
-int stats_dump_raw(struct session *s, struct buffer *rep, struct uri_auth *uri);
-void stats_dump_raw_to_buffer(struct session *s, struct buffer *req);
+int stats_dump_raw_to_buffer(struct session *s, struct buffer *rep);
 int stats_dump_http(struct session *s, struct buffer *rep, struct uri_auth *uri);
 int stats_dump_proxy(struct session *s, struct proxy *px, struct uri_auth *uri);
 int stats_dump_sess_to_buffer(struct session *s, struct buffer *rep);