Update mod_auth_kerb to include debian install fixes

diff --git a/mod_auth_kerb b/mod_auth_kerb
index 82dee36..552ba77 160000 (submodule)
--- a/mod_auth_kerb
+++ b/mod_auth_kerb
@@ -1 +1 @@
-Subproject commit 82dee36eff56c3ef87dd242077a8e306208369fe
+Subproject commit 552ba77f11f6cad71a1ad7d69457cde840242182