nodedev: Alter node device deletion logic

nodedev: Alter node device deletion logic

Alter the node device deletion logic to make use of the parent field
from the obj->def rather than call virNodeDeviceObjListGetParentHost.
As it turns out the saved @def won't have parent_wwnn/wwpn or
parent_fabric_wwn, so the only logical path would be to call
virNodeDeviceObjListGetParentHostByParent which we can accomplish
directly via virNodeDeviceObjListFindByName.