Winsock needs a couple more tweaks

and no_opattrs. Presumably some internal ops with only one or the other
flag set should still get logged, but if both are set, logging is skipped.

registered the control for a specific BackendDB to make sure that
the control is unregistered only after the last instance calls
overlay_unregister_control().

on entryInfo, otherwise BDB locks in reader txn are released too soon

sssvlv overlay

needed for cn=config delete support

Those require some special handling.