[2498] Add naptr to factory_users list

src/lib/dns/gen-rdatacode.py.in

@@ -34,6 +34,7 @@ import sys
 #     new_rdata_factory_users = [('a', 'in'), ('a', 'ch'), ('soa', 'generic')]
 new_rdata_factory_users = [('aaaa', 'in'),
                            ('hinfo', 'generic'),
+                           ('naptr', 'generic'),
                            ('spf', 'generic'),
                            ('txt', 'generic')
                           ]