libidn 1.36 on Solaris 11.4

[Bruno Haible]

On Solaris 11.4, the build fails like this:

gmake[3]: Entering directory '/export/home/bruno/libidn-1.36/build-64/lib'
  CC       nfkc.lo
  CC       toutf8.lo
  CC       version.lo
  CC       stringprep.lo
  CC       rfc3454.lo
  CC       profiles.lo
  CC       punycode.lo
  CC       idna.lo
  CC       pr29.lo
  CC       idn-free.lo
  CC       strerror-idna.lo
  CC       strerror-pr29.lo
  CC       strerror-punycode.lo
  CC       strerror-stringprep.lo
  CC       strerror-tld.lo
  CC       tld.lo
  CC       tlds.lo
  CCLD     libidn.la
../libtool[1720]: eval: syntax error at line 1: `|' unexpected
gmake[3]: *** [Makefile:1621: libidn.la] Error 3

The fix is to use attachment 42206 from <http://savannah.gnu.org/patch/?9467>
(on top of the newest libtool release 2.4.6).

Bruno