Add intersphinx_mapping

This was we can reference the ric project from the index of
the doc project

Signed-off-by: Aric Gardner <agardner@linuxfoundation.org>
Change-Id: I8ed91f83ac20a11b1e998feb759342f8956527ff
diff --git a/docs/conf.py b/docs/conf.py
index 3c4453e..e2da8e9 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -1 +1,10 @@
 from docs_conf.conf import *
+
+branch = 'latest'
+
+linkcheck_ignore = [
+      'http://localhost',
+]
+
+intersphinx_mapping = {}
+intersphinx_mapping['portal-ric-dashboard'] = ('https://o-ran-sc-doc-test.readthedocs.io/projects/o-ran-sc-portal-ric-dashboard-test/en/%s' % branch, None)