configure.in: default os_version_style
/usr/bin/ruby
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45352 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
configure.in: default os_version_style
/usr/bin/ruby
if possible.git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45352 b2dd03c8-39d4-4d8f-98ff-823fe69b080e