Remove link to modindex
Remove link to modindex

The documentation build does not generate any module index, thus
remove the link to the page.

Change-Id: I7508fc6025f86fd1ef50ac372c35e7a8f0a8a056

szaher/freezer-api,openstack/freezer-api,szaher/freezer-api,openstack/freezer-api,szaher/freezer-api,szaher/freezer-api,openstack/freezer-api,openstack/freezer-api