Promote Mac Catalyst targets to Tier 2, and ship with rustup Promote the Mac Catalyst targets `x86_64-apple-ios-macabi` and `aarch64-apple-ios-macabi` to Tier 2, as per [the MCP](https://github.com/rust-lang/compiler-team/issues/761) (see that for motivation and details). These targets are now also distributed with rustup, although without the sanitizer runtime, as that currently has trouble building, see https://github.com/rust-lang/rust/issues/129069.