update vkh

diff --git a/vkh b/vkh
index d4c367287ea50e854205e27cf814abbb23615b8a..e448f9f0e10fbc1d0a62ce471c73880d207e7d66 160000 (submodule)
--- a/vkh
+++ b/vkh
@@ -1 +1 @@
-Subproject commit d4c367287ea50e854205e27cf814abbb23615b8a
+Subproject commit e448f9f0e10fbc1d0a62ce471c73880d207e7d66