Remove `rustc_error_codes` deps except in `rustc_driver`
Remove dependencies on `rustc_error_codes` in all crates except for `rustc_driver`.
This has some benefits:
1. Adding a new error code when hacking on the compiler only requires rebuilding at most `rustc_error_codes`, `rustc_driver`, and the reflexive & transitive closure of the crate where the new error code is being added and its reverse dependencies. This improves time-to-UI-tests (TTUT).
2. Adding an error description to an error code only requires rebuilding `rustc_error_codes` and `rustc_driver`. This should substantially improve TTUT.
r? @petrochenkov
cc @rust-lang/wg-diagnostics