test_rbconfig.rb: honor configuration options

* test/test_rbconfig.rb (TestRbConfig): skip user defined values by
  configuration options.  [Bug #7902]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39372 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* tool/mkrunnable.rb: refactor and multiarch support.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39373 b2dd03c8-39d4-4d8f-98ff-823fe69b080e