Add separate release notes page for v11.0.0

This commit makes a separate page in the generated release note docs
for the v11.0.0 release.

Change-Id: I7dabe26dbe1f08efea2aa99730fde0269b26ce6c
diff --git a/releasenotes/source/v11.0.0.rst b/releasenotes/source/v11.0.0.rst
new file mode 100644
index 0000000..84b145d
--- /dev/null
+++ b/releasenotes/source/v11.0.0.rst
@@ -0,0 +1,6 @@
+=====================
+v11.0.0 Release Notes
+=====================
+
+.. release-notes:: 11.0.0 Release Notes
+   :version: 11.0.0