Log Message:
libidn: update to 1.38.

* Noteworthy changes in release 1.38 (2021-07-22) [stable]

** doc: Simplify building of gdoc-generated man/texi outputs.
Now the targets are rebuilt on version number changes properly.

** doc: Improve GTK-DOC manual.

** build: Fix build errors related to doc/idn--help.texi.

** build: Fix --disable-tld builds.
Now tld_strerror() is removed when --disable-tld is used.