remove dns_sdb
The dns_sdb API is no longer used anywhere except for the builtin databases (empty zones, hostname.bind, version.bind, etc). We can refactor builtins to implement dns_db directly and get rid of the dns_sdb API.
The dns_sdb API is no longer used anywhere except for the builtin databases (empty zones, hostname.bind, version.bind, etc). We can refactor builtins to implement dns_db directly and get rid of the dns_sdb API.