Special casing for Ironic VIRT_DRIVER in exercises

Ironic on Devstack does not currently suppport security groups or
anything volume related.  Add some special casing so exercises can
be run without error against the Ironic driver.

Change-Id: I2a54d8cca06fc17894e74b4401af9423cef95635
diff --git a/exercises/euca.sh b/exercises/euca.sh
index 3768b56..f9c4752 100755
--- a/exercises/euca.sh
+++ b/exercises/euca.sh
@@ -36,6 +36,9 @@
 # Import exercise configuration
 source $TOP_DIR/exerciserc
 
+# Import project functions
+source $TOP_DIR/lib/neutron
+
 # If nova api is not enabled we exit with exitcode 55 so that
 # the exercise is skipped
 is_service_enabled n-api || exit 55
@@ -82,7 +85,7 @@
 
 # Volumes
 # -------
-if is_service_enabled c-vol && ! is_service_enabled n-cell; then
+if is_service_enabled c-vol && ! is_service_enabled n-cell && [ "$VIRT_DRIVER" != "ironic" ]; then
     VOLUME_ZONE=`euca-describe-availability-zones | head -n1 | cut -f2`
     die_if_not_set $LINENO VOLUME_ZONE "Failure to find zone for volume"