[automerge] Revert "Use libbitflags-1.3.2" 2p: a67abce652

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/rust/crates/nix/+/23215390

Change-Id: I6c0d33e1a3778f73175e62d2e0a4bd2a661d16c6