Pick up libvirtd group membership when running cleanup

Change-Id: Ic36d2fe67c6215dbaff84f6f83fa75aefd8b7e9d
diff --git a/scripts/cord-in-a-box.sh b/scripts/cord-in-a-box.sh
index 7c475da..c37fb98 100755
--- a/scripts/cord-in-a-box.sh
+++ b/scripts/cord-in-a-box.sh
@@ -12,7 +12,7 @@
 
   echo "Destroying all Vagrant VMs"
   cd $CORDDIR/build
-  vagrant destroy
+  sudo su $USER -c 'vagrant destroy'
 
   echo "Removing $CORDDIR"
   cd ~
@@ -28,7 +28,6 @@
 
   [ -e ~/.ssh/id_rsa ] || ssh-keygen -t rsa -N "" -f ~/.ssh/id_rsa
 
-  USER=$(whoami)
   sudo adduser $USER libvirtd
 
   sudo curl -o /usr/local/bin/repo https://storage.googleapis.com/git-repo-downloads/repo