Fix non-standard code in report().

diff --git a/programs/winetest/gui.c b/programs/winetest/gui.c
index 9618d7c..0980f32a 100644
--- a/programs/winetest/gui.c
+++ b/programs/winetest/gui.c
@@ -417,6 +417,7 @@
         funcs = quiet_funcs;
         return 0;
     default:
+        break;
     }
 
     if (!funcs) {