update vkh

diff --git a/vkh b/vkh
index 5d84e42590eff42cdb02a3c10227de0c1ca1737a..4824a7ec5b113892f2fdac0059f0e0f88a490625 160000 (submodule)
--- a/vkh
+++ b/vkh
@@ -1 +1 @@
-Subproject commit 5d84e42590eff42cdb02a3c10227de0c1ca1737a
+Subproject commit 4824a7ec5b113892f2fdac0059f0e0f88a490625