Correction for custom charts, the variable is never empty

Change-Id: Id1fdaba892d2e583b0dfe337e69c8f1cd1f51d70
diff --git a/jjb/voltha-test/voltha-nightly-jobs.yaml b/jjb/voltha-test/voltha-nightly-jobs.yaml
index 5d4a1fd..978aaf4 100644
--- a/jjb/voltha-test/voltha-nightly-jobs.yaml
+++ b/jjb/voltha-test/voltha-nightly-jobs.yaml
@@ -7,6 +7,8 @@
 
     openoltAdapterChart: onf/voltha-adapter-openolt
 
+    oltAdapterReleaseName: open-olt
+
     parameters:
       - string:
           name: buildNode
@@ -168,7 +170,12 @@
       - string:
           name: openoltAdapterChart
           default: '{openoltAdapterChart}'
-          description: 'OpenOLT chart name (or location on file system)'
+          description: 'Olt adapter chart name (or location on file system)'
+
+      - string:
+          name: oltAdapterReleaseName
+          default: '{oltAdapterReleaseName}'
+          description: 'Olt adapter release name'
 
 # defualt properties for the VOLTHA scale jobs
 - voltha-pipe-job-boiler-plate: &voltha-pipe-job-boiler-plate