configure.in: move opt-dir option
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44257 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
configure.in: move opt-dir option
not only after rbconfig.rb.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44257 b2dd03c8-39d4-4d8f-98ff-823fe69b080e