Rollup merge of #133207 - jieyouxu:macos-objcopy, r=Kobzol,bjorn3

Default-enable `llvm_tools_enabled` when no `config.toml` is present

Fixes #133195. cc `@wesleywiser` could you double check if with this patch and no `config.toml` that you can run `./x test tests/ui --stage 1`?

`llvm-objcopy` is usually required by cg_ssa on macOS to workaround bad `strip`s.

cc `@bjorn3` I hope this doesn't break cg_clif...

r? bootstrap

Author: matthiaskrgr