Set stdout/stdin to binary mode on Windows

Summary:
A file opened in text mode on Windows will have `\n` automatically changed to `13,10` while Darwin and Linux leave it as `10`.

Set the file to binary mode to avoid this automatic conversion so that Darwin, Linux and Windows have equivalent treatment of `\r`.

Reviewers: clayborg, xiaobai

Reviewed By: clayborg

Subscribers: emaste, ki.stfu, mgorny, eraman, JDevlieghere, mgrang

Differential Revision: https://reviews.llvm.org/D52672

llvm-svn: 346174