Create cord-6.0 support branch

Only checks out cord-6.0 branch for these project repos:

 - automation-tools
 - docs
 - helm-charts

If more cord-6.0 branches are created on other project repos, must
update manifest.xml

Change-Id: I858c2b93a3995f2b31e8ce521f2a1adb36bf8ab8
diff --git a/default.xml b/default.xml
index c8a277a..b7a6d23 100644
--- a/default.xml
+++ b/default.xml
@@ -9,9 +9,9 @@
            remote="opencord"
            sync-j="4" />
 
-<project path="helm-charts" name="helm-charts" groups="build"/>
-<project path="automation-tools" name="automation-tools" groups="build"/>
-<project path="docs" name="docs" groups="build"/>
+<project path="helm-charts" name="helm-charts" revision="cord-6.0" groups="build"/>
+<project path="automation-tools" name="automation-tools" revision="cord-6.0" groups="build"/>
+<project path="docs" name="docs" revision="cord-6.0" groups="build"/>
 
 <project path="onos-apps" name="cord-onos-publisher" groups="onos"/>
 <project path="onos-apps/apps/aaa" name="aaa" groups="onos"/>