Calling set_max_level can result in a race condition on platforms that don't have an atomic compare and swap implementation. This gates set_max_level behind #[cfg(atomic_cas)] and adds a racy alternative that can be called in these situations. This mirrors the approach for set_logger.
Calling
set_max_levelcan result in a race condition on platforms that don't have an atomic compare and swap implementation. This gatesset_max_levelbehind#[cfg(atomic_cas)]and adds a racy alternative that can be called in these situations. This mirrors the approach forset_logger.Fixes #534