add oam docs

Signed-off-by: weichen <niweichen@chinamobile.com>
Change-Id: Ia4e9ff8083c39be3f7990093125bc7ceaff03ed3
diff --git a/docs/projects.rst b/docs/projects.rst
index 709856e..f090fbc 100644
--- a/docs/projects.rst
+++ b/docs/projects.rst
@@ -58,6 +58,7 @@
 
 More detailed function documentation can be found as follow:
 
+* :doc:`OAM Operation and Maintenance <oam:index>`
 * :doc:`RIC Dashboard <portal-ric-dashboard:index>`