Fix problem where rvitals fails to gracefully handle situations like timeout on a sensor read

git-svn-id: https://svn.code.sf.net/p/xcat/code/xcat-core/trunk@13810 8638fb3e-16cb-4fca-ae20-7b5d299a9bcd

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

@@ -4448,6 +4448,7 @@ sub sensor_was_read {
     my $sessdata = shift;
     if ($rsp->{error}) {
         xCAT::SvrUtils::sendmsg([1,$rsp->{error}],$callback,$sessdata->{node},%allerrornodes);
+	return;
     }
     if ($rsp->{code}) {
         my $text = $codes{$rsp->{code}};