Time Sync object can be created only if DLR object is available

Currently it is not possible to create the Time Sync object without also supporting the DLR object.

When the Time Sync object is created it tries to get the DLR handle and returns an error in case this is not successful.

The Time sync must access the DLR object in case DLR is supported. This is necessary as the Time Sync object needs information about changing topology events (e.g. Ring break).

However, in case DLR is not supported, the Time Sync object must not insist of accessing the DLR object.