When dig was built without IDN support, it reported an error if the
+noidnin and/or +noidnout options were used. This means the options
were not useful for a script that wants consistent lack of IDN
translation regardless of how BIND is built.
Make dig complain about lack of built-in IDN support only when the
user asks for IDN translation.
Closes#3188
Tony Finch
ae73a8d87a