add license claim to overview.rst

Signed-off-by: weichen <niweichen@chinamobile.com>
Change-Id: Id53ab352ea97dbdaea952b2f64c951c6c791d555
diff --git a/doc-templates/overview.rst b/doc-templates/overview.rst
index f29301e..6d620a1 100644
--- a/doc-templates/overview.rst
+++ b/doc-templates/overview.rst
@@ -1,3 +1,7 @@
+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. SPDX-License-Identifier: CC-BY-4.0
+
+
 ..please write your project overview
 ..please delete this content after editing