bug 1494442: fix attach/detach disks automate methods

Fix for bug 1494442 - symbol conversion error while detaching disks
  from an openstack instance

https://bugzilla.redhat.com/show_bug.cgi?id=1494442

app/models/manageiq/providers/openstack/cloud_manager.rb

@@ -342,13 +342,13 @@ def vm_delete_evm_snapshot(vm, image_id)
     raise
   end
 
-  def vm_attach_volume(vm, volume_id, device = nil)
-    volume = find_by_id_filtered(CloudVolume, volume_id)
-    volume.raw_attach_volume(vm.ems_ref, device)
+  def vm_attach_volume(vm, options)
+    volume = CloudVolume.find_by(:id => options[:volume_id])
+    volume.raw_attach_volume(vm.ems_ref, options[:device])
   end
 
-  def vm_detach_volume(vm, volume_id)
-    volume = find_by_id_filtered(CloudVolume, volume_id)
+  def vm_detach_volume(vm, options)
+    volume = CloudVolume.find_by(:id => options[:volume_id])
     volume.raw_detach_volume(vm.ems_ref)
   end