cyrus: add server FQDN as realm if we don't have one

diff --git a/cyrus-sasl b/cyrus-sasl
index 7098ec6..9da0e79 160000 (submodule)
--- a/cyrus-sasl
+++ b/cyrus-sasl
@@ -1 +1 @@
-Subproject commit 7098ec6a42fb9edd2fd2b4108f84ac3ba8271bb4
+Subproject commit 9da0e79067688db69a6ea1437de2780af4fa80b7