Make re-runs of the script possible without -c

Change-Id: I9180324818398da17164b5dda43584e0d9bc6954
diff --git a/scripts/single-node-pod.sh b/scripts/single-node-pod.sh
index d810d04..bb1a312 100755
--- a/scripts/single-node-pod.sh
+++ b/scripts/single-node-pod.sh
@@ -35,9 +35,8 @@
     [ -e ~/.ssh/id_rsa ] || ssh-keygen -t rsa -N "" -f ~/.ssh/id_rsa
     cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
 
-    git clone $SETUP_REPO_URL platform-install
+    [ -d platform-install ] || git clone -b $SETUP_BRANCH $SETUP_REPO_URL platform-install
     cd ~/platform-install
-    git checkout $SETUP_BRANCH
 
     sed -i "s/replaceme/`whoami`/" $INVENTORY