Mark has committed this now, I'm resolving the ticket. Thanks.

4801.   [func]          'dnssec-lookaside auto;' and 'dnssec-lookaside .
                        trust-anchor dlv.isc.org;' now elicit warnings rather
                        than being fatal configuration errors. [RT #46410]

9.12.0, 9.11.3, 9.10.7, 9.9.12