configure.in: find Setup file automatically
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39486 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
configure.in: find Setup file automatically
suffix (e.g. Setup.nacl, Setup.atheos), 2. by "platform"
option (e.g. Setup.nt, Setup.emx), and 3. default Setup. And
Setup.dj had been removed.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39486 b2dd03c8-39d4-4d8f-98ff-823fe69b080e