Fix wvid hang on KVM guests if guest is off

git-svn-id: https://svn.code.sf.net/p/xcat/code/xcat-core/trunk@9522 8638fb3e-16cb-4fca-ae20-7b5d299a9bcd

xCAT-server/lib/xcat/plugins/kvm.pm

@@ -693,8 +693,8 @@ sub getcons {
 sub getrvidparms {
     my $node=shift;
     my $location = getcons($node,"vid");
-    unless ($location) {
-       return (1,"Error: Unable to determine rvid destination for $node");
+    unless (ref $location) {
+       return (1,"Error: Unable to determine rvid destination for $node (appears VM is off)");
     }
         my @output = (
       "method: kvm"