type error go brrrrrrrr Fixes #90444 when we relate something like: `fn(fn((), (), u32))` with `fn(fn((), (), ()))` we relate the inner fn ptrs: `fn((), (), u32)` with `fn((), (), ())` yielding a `TypeError::ArgumentSorts(_, 2)` which we then use as the `TypeError` for the `fn(fn(..))` which later causes the ICE as the `2` does not correspond to any input or output types in `fn(_)` r? `@estebank`
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