CLOUDSTACK-2558 Nexus configuration cleanup is not done when there is a failure while adding the Nexus enabled VMWARE cluster which is causing for NPE while readding the cluster with same configuration details

If cluster addition fails then cleaning up the Nexus VSM related to the cluster.

Signed-off-by: Sateesh Chodapuneedi <sateesh@apache.org>
CLOUDSTACK-2729: use spd.getTargetPath instead of mount path to fix issue on local storage