fix(ggml): don't use Neon on macOS aarch64

This code doesn't feel right. The original order pre-#426 should work -
why would mcpu=native not work in that case?

I think this is something that will need revisiting.

crates/ggml/sys/build.rs

@@ -77,9 +77,9 @@ fn main() {
  if compiler.is_like_clang() || compiler.is_like_gnu() {
  if target_os == "macos" {
  build.flag("-mcpu=apple-m1");
- build.flag("-mfpu=neon");
  } else if std::env::var("HOST") == std::env::var("TARGET") {
  build.flag("-mcpu=native");
+ build.flag("-mfpu=neon");
  }
  build.flag("-pthread");
  }