Enable the deferred fatality of missing glue / servers from BIND 9.5.0
Missing glue on referral and address record on SRV records was supposed to be made fatal in BIND 9.5.0.
See the comments in lib/dns/zone.c of the form "/* XXX950 make fatal for 9.5.0. */"
Delegating NS records that refer to CNAMEs or names below DNAMEs, NS records that provably refer to names in the parent zone that don't exist or don't have address records, and missing glue records where all intended to be made fatal errors when loading a primary zone in BIND 9.5.0. They either make the delegation fail or make it less robust (perceived redundancy is not present). Additionally many users expect named-checkzone to reject such broken delegations when they can be detected. These checks are controlled by check-integrity, check-sibling determines if address records under sibling delegations are also checked for.
These configuration errors where made warnings during the 9.4.0 maintenance period.
Additionally SRV records which refer to non-existing names or names without addresses where also flagged to be made fatal errors for primary zones. Again this is done under the check-integrity umbrella. Again many users expect named-checkzone to fail on such obvious errors.