Update perkamon to manpages 3.68

diff --git a/perkamon b/perkamon
index 91419a0..6c1f919 160000 (submodule)
--- a/perkamon
+++ b/perkamon
@@ -1 +1 @@
-Subproject commit 91419a08041d024741ba66ceefa98c22bb0a0f03
+Subproject commit 6c1f9199dca4be8941399d9e439d408d92ef0039