win32.h: fstat on mingw32
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37337 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
win32.h: fstat on mingw32
on mingw32.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37337 b2dd03c8-39d4-4d8f-98ff-823fe69b080e