* ext/openssl/ossl_rand.c: Use rb_define_module_function instead of
  macro. [Fixes GH-686] https://github.com/ruby/ruby/pull/686


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47780 b2dd03c8-39d4-4d8f-98ff-823fe69b080e