configure.in: repeated checks
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57092 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
configure.in: repeated checks
RUBY_DTRACE_AVAILABLE checks.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57092 b2dd03c8-39d4-4d8f-98ff-823fe69b080e