feat: sync from upstream to support openresty-1.25.3 (#13)

Author: zll600

README.md

@@ -1,4 +1,4 @@
-This project is exacted from [tengine](https://github.com/alibaba/tengine/tree/master/modules/ngx_multi_upstream_module) since tengine-2.3.2.
+This project is exacted from [tengine](https://github.com/alibaba/tengine/tree/master/modules/ngx_multi_upstream_module) since tengine-2.4.0.
 
 # ngx_multi_upstream_module
 ngx_multi_upstream_module for nginx

ngx_http_multi_upstream_module.c

@@ -452,9 +452,6 @@ ngx_http_multi_upstream_init_connection(ngx_connection_t *c,
     fake_u->peer.connection = c;
 #if (NGX_HAVE_FILE_AIO || NGX_COMPAT)
     fake_u->output.aio_handler = u->output.aio_handler;
-#if (NGX_HAVE_AIO_SENDFILE || NGX_COMPAT)
-    fake_u->output.aio_preload = u->output.aio_preload;
-#endif
 #endif
 
 #if (NGX_THREADS || NGX_COMPAT)