整理stream处理流程，适应KNI接口定义。

platform/include/internal/stream.h

@@ -78,6 +78,8 @@ struct tfe_conn_private
 struct tfe_stream_private
 {
 	struct tfe_stream head;
+	struct tfe_proxy *proxy;
+
 	enum tfe_session_proto session_type;
 	struct tfe_conn_private conn_upstream;
 	struct tfe_conn_private conn_downstream;
@@ -96,11 +98,14 @@ struct tfe_stream_private
 
 	uint8_t is_plugin_opened;
 	int calling_idx;
+
 	size_t forward_bytes;
 	size_t defere_bytes;
 	size_t drop_bytes;
+
 	enum tfe_app_proto app_proto;
 	int plugin_num;
+
 	struct plugin_ctx * plug_ctx;
 	unsigned char passthrough;      /* 1 if SSL passthrough is active */