fix variable access_log merging

src/http/modules/ngx_http_log_module.c

diff --git a/src/http/modules/ngx_http_log_module.c b/src/http/modules/ngx_http_log_module.c
index f4eefde..f0fd565 100644
--- a/src/http/modules/ngx_http_log_module.c
+++ b/src/http/modules/ngx_http_log_module.c
@@ -761,7 +761,8 @@
         return NGX_CONF_OK;
     }
 
-    *conf = *prev;
+    conf->logs = prev->logs;
+    conf->off = prev->off;
 
     if (conf->logs || conf->off) {
         return NGX_CONF_OK;