Add support for compiling on Apple Silicon. Defines new platform `darwin_arm64`.
Add support for compiling on Apple Silicon.
Defines new platform `darwin_arm64`.

RELNOTES: Add support to bazel/crosstool for building arm64 on macos aka darwin
PiperOrigin-RevId: 320064480

bazelbuild/rules_apple,bazelbuild/rules_apple,bazelbuild/rules_apple,bazelbuild/rules_apple