Fixed getVolthaCode to take correct voltha-helm-charts branch, and updated versions for software upgrade jobs

Change-Id: Idc3946272909b76231f7b714944389a658201b10
diff --git a/vars/getVolthaCode.groovy b/vars/getVolthaCode.groovy
index 815e719..d763429 100644
--- a/vars/getVolthaCode.groovy
+++ b/vars/getVolthaCode.groovy
@@ -82,7 +82,7 @@
       userRemoteConfigs: [[
         url: "https://gerrit.opencord.org/voltha-helm-charts",
       ]],
-      branches: [[ name: "master", ]],
+      branches: [[ name: "${cfg.branch}", ]],
       extensions: [
         [$class: 'WipeWorkspace'],
         [$class: 'RelativeTargetDirectory', relativeTargetDir: "voltha-helm-charts"],