update vkh

diff --git a/vkh b/vkh
index 681d3b8f22bf29f04a329464239cabaf38beeb45..2a194890dfed6eb82d3a92fd56ecc46f47735d29 160000 (submodule)
--- a/vkh
+++ b/vkh
@@ -1 +1 @@
-Subproject commit 681d3b8f22bf29f04a329464239cabaf38beeb45
+Subproject commit 2a194890dfed6eb82d3a92fd56ecc46f47735d29