configure.in: move RUBY_PLATFORM to config.h
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40763 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
configure.in: move RUBY_PLATFORM to config.h
version.c.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40763 b2dd03c8-39d4-4d8f-98ff-823fe69b080e