[emacs] Update ebdb to 0.6-21-g980927f

diff --git a/lib/ebdb b/lib/ebdb
index 3289ad4..980927f 160000 (submodule)
--- a/lib/ebdb
+++ b/lib/ebdb
@@ -1 +1 @@
-Subproject commit 3289ad49daf8a669126b8fc929d7f80f60b82797
+Subproject commit 980927ff3dfdb238e7b168f0088353fec29db86e