Use bazel starlark flags instead of defines

Inspired by https://github.com/bazelbuild/rules_apple/commit/4287aa277e14c693a9c036a8382521964c6951b3, I figure it'd be worthwhile to track this somewhere.

In the case of this commit, instead of:
```
--define=apple.package_symbols=yes
```

It would be, for instance:
```
--@build_bazel_rules_apple//config:package_symbols=true
```

`rules_go` has it now and it's very nice to use: https://github.com/bazelbuild/rules_go/blob/8f4ebbd09b1a82a684f839c3eadddc6db7277c3a/go/modes.rst#building-pure-go-binaries

Start by comparing the referenced rules_apple commit with rules_go's go/modes.rst to understand the Starlark flag pattern. Identify the Apple rules and configuration points using --define, then replace the relevant flags with Starlark flags and verify that the documented usage still works.

Written by the indexing model from the issue text.