[roll] Roll llvm-project/libc [libc] Migrate from baremetal stdio.h to generic stdio.h (#152748)

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

GitOrigin-RevId: 020dff4be832e035a24fcdb13e26d7c2e69887eb
Original-Revision: d884b3e1b59aeca6a985e7dbfc3a20827ae5095b

Rolled-Repo: https://llvm.googlesource.com/llvm-project/libc
Rolled-Commits: b40c9b8d009430..d884b3e1b59aec
Roller-URL: https://cr-buildbucket.appspot.com/build/8704929101953615937
CQ-Do-Not-Cancel-Tryjobs: true
Cq-Include-Trybots: luci.turquoise.global.try:run-postsubmit-tryjobs
Change-Id: I8ead7ea715ded9dbcdfe893b80fbec8012e1adc2
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1358156
Commit-Queue: GI Roller <[email protected]>

Author: William Huynh

manifests/third_party/all

@@ -295,7 +295,7 @@
     <project name="llvm-project/libc"
              path="third_party/llvm-libc/src"
              remote="https://llvm.googlesource.com/llvm-project/libc"
-             revision="b40c9b8d009430302e7d1917a4e37b9120fe982b"/>
+             revision="d884b3e1b59aeca6a985e7dbfc3a20827ae5095b"/>
     <project name="third_party/luci-go"
              path="third_party/luci-go"
              revision="fd977bf9e01d199a529f28af6dc10fe0fa35d9e7"