CORD-391 - cleaned up ansible to pass cleanly through ansible-lint

Change-Id: I90284704255edc19abbdb239852c520a4bf48df4
diff --git a/roles/compute-node/tasks/mlx4_driver.yml b/roles/compute-node/tasks/mlx4_driver.yml
index 06219d2..a9b76f0 100644
--- a/roles/compute-node/tasks/mlx4_driver.yml
+++ b/roles/compute-node/tasks/mlx4_driver.yml
@@ -17,6 +17,7 @@
 - name: Install mlx4 driver
   become: yes
   command: /tmp/mlnx-en-3.1-1.0.4/install.sh --batch
+  changed_when: true
 
 - name: Remove Build Directory
   become: yes