iar-docker-images: Build image on EC2 node

Signed-off-by: Arthur She <arthur.she@linaro.org>
Change-Id: I5eb8312dc4b5bcc231afa85d1f7364904c380ef1
diff --git a/iar-docker-images.yaml b/iar-docker-images.yaml
index efddf2f..4de7470 100644
--- a/iar-docker-images.yaml
+++ b/iar-docker-images.yaml
@@ -8,8 +8,9 @@
             num-to-keep: 30
     disabled: false
     # Test build job on TF-02
-    node: build-amd64
-#    node: build-amd64-private
+    #    node: build-amd64
+    # Run on EC2
+    node: build-amd64-private
     concurrent: false
     display-name: 'TF-M IAR Docker images build job'
     parameters: