Fix logic on alt user tenant/password check.

Updates the setup_package function so that the password/tenant
check for the alternate user works correctly. Previously it
was checking for a missing password but present tenant. It should
check for a missing password or missing tenant.

Change-Id: I3ab28baa13a66077d4a46e8fd2a40ec4869b9c70
diff --git a/tempest/tests/compute/__init__.py b/tempest/tests/compute/__init__.py
index fd6912d..e196bd5 100644
--- a/tempest/tests/compute/__init__.py
+++ b/tempest/tests/compute/__init__.py
@@ -73,7 +73,7 @@
         if user2 and user1 != user2:
             user2_password = CONFIG.compute.alt_password
             user2_tenant_name = CONFIG.compute.alt_tenant_name
-            if not user2_password or user2_tenant_name:
+            if not user2_password or not user2_tenant_name:
                 msg = ("Alternate user specified but not alternate "
                        "tenant or password")
                 raise nose.SkipTest(msg)