build: disable swift-numerics on Darwin targets (#1060)
build: disable swift-numerics on Darwin targets (#1060)

Disable the bundled swift-numerics by defualt on Darwin targets.  This repairs
the build as `-force-autoload-symbol` and `-incremental` are not currently
supported on Darwin.
tensorflow/swift-apis,tensorflow/swift-apis,tensorflow/swift-apis,tensorflow/swift-apis,tensorflow/swift-apis