Except for `simd-intrinsic/`, which has a lot of files containing
multiple types like `u8x64` which really are better when hand-formatted.
There is a surprising amount of two-space indenting in this directory.
Non-trivial changes:
- `rustfmt::skip` needed in `debug-column.rs` to preserve meaning of the
test.
- `rustfmt::skip` used in a few places where hand-formatting read more
nicely: `enum/enum-match.rs`
- Line number adjustments needed for the expected output of
`debug-column.rs` and `coroutine-debug.rs`.
`[T; N]::zip` is "eager" but most zips are mapped.
This causes poor optimization in generated code.
This is a fundamental design issue and "zip" is
"prime real estate" in terms of function names,
so let's free it up again.