This is a follow up to the RFC here: https://discourse.llvm.org/t/rfc-implementation-of-stdio-on-baremetal/86944 This provides the stdout/stderr/stdin symbols (which now don't have to provided by the user). This allows the user to have access to all functions, currently I've only tested `fprintf` but in theory everything that works in the generic folder should work in the baremetal configuration. All streams are _non-buffered_, which does NOT require flushing. It is based on the CookieFile that already existed