conf: checkpoint: Don't clear current checkpoint when redefining an existing one

There's no point in clearing the current checkpoint when we are just
changing the definition of the current checkpoint as by the virtue of the
'update_current' flag the same checkpoint would become current in
qemuCheckpointCreateXML.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

src/conf/checkpoint_conf.c

@@ -569,11 +569,6 @@ virDomainCheckpointRedefinePrep(virDomainObjPtr vm,
                                            def->parent.dom, xmlopt))
             return -1;
 
-        if (other == virDomainCheckpointGetCurrent(vm->checkpoints)) {
-            *update_current = true;
-            virDomainCheckpointSetCurrent(vm->checkpoints, NULL);
-        }
-
         /* Drop and rebuild the parent relationship, but keep all
          * child relations by reusing chk.  */
         virDomainMomentDropParent(other);