configure.in: remove no longer used variable
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39514 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
configure.in: remove no longer used variable
used since r39506. [Bug #7959]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39514 b2dd03c8-39d4-4d8f-98ff-823fe69b080e