[stdlib] Suppress noisy warnings
[stdlib] Suppress noisy warnings

We don't have a way yet to say "this is deprecated for users, but let
the stdlib use it without complaining" so we need to do refactoring
shenanigans.

apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation