Update 2.11 release notes

Change-Id: I26426e5b8fbf877b2819bd4cbb775cdc94cf41b6
diff --git a/ReleaseNotes/ReleaseNotes-2.11.txt b/ReleaseNotes/ReleaseNotes-2.11.txt
index abfeb42..6071d8a 100644
--- a/ReleaseNotes/ReleaseNotes-2.11.txt
+++ b/ReleaseNotes/ReleaseNotes-2.11.txt
@@ -556,6 +556,19 @@
 the documentation], if more than one `footer` token was specified in the
 `trackingid` section, only the first was used.
 
+* Treat empty
+link:https://gerrit-documentation.storage.googleapis.com/Documentation/2.11/config-gerrit.html#hooks[
+`hooks.*`] values as missing, rather than trying to execute the hooks
+directory.
+
+* Fix `changed-merged` hook configuration.
++
+Contrary to the
+link:https://gerrit-documentation.storage.googleapis.com/Documentation/2.11/config-gerrit.html#hooks[
+documentation], the changed-merged hook configuration value was being
+read from `hooks.changeMerged`. Fix to use `hooks.changeMergedHook` as
+documented.
+
 Web UI
 ~~~~~~