Matthew Clarkson authored Dec 13, 2023 and Matthew Clarkson committed Dec 13, 2023

Brings along some simplification to the project in terms of registering
the various toolchains.

For `busybox`/`coreutils` we no longer provide the local overrides.

We have macros for registering each core utility against `coreutils`/`busybox`
so that the toolchain resolution will gracefully fallback if there is no
toolchain for the current platform.