Adding SALT_MASTER_CREDENTIALS to test-virtual-model

Change-Id: I676ed1b50d704da4e5e7451538ad77af68cdcdc8
diff --git a/jenkins/client/job/oscore/salt_virtual_models.yml b/jenkins/client/job/oscore/salt_virtual_models.yml
index 180b2da..d8a2d9d 100644
--- a/jenkins/client/job/oscore/salt_virtual_models.yml
+++ b/jenkins/client/job/oscore/salt_virtual_models.yml
@@ -19,6 +19,10 @@
           display_name: oscore-test-virtual-model
           name: oscore-test-virtual-model
           param:
+            SALT_MASTER_CREDENTIALS:
+              type: string
+              default: "salt-qa-credentials"
+              description: Jenkins credential ID for Salt master
             CREDENTIALS_ID:
               default: gerrit
               type: string