Rollup merge of #117414 - compiler-errors:tait-forevert, r=oli-obk

Don't normalize to an un-revealed opaque when we hit the recursion limit

Currently, we will normalize `Opaque := Option<&Opaque>` to something like `Option<&Option<&Option<&...Opaque>>>`, hitting a limit and bottoming out in an unnormalized opaque after the recursion limit gets hit.

Unfortunately, during `layout_of`, we'll simply recurse and try again if the type normalizes to something different than the type:
https://github.com/rust-lang/rust/blob/e6e931dda5fffbae0fd87c5b1af753cc95556880/compiler/rustc_ty_utils/src/layout.rs#L58-L60

That means then we'll try to normalize `Option<&Option<&Option<&...Opaque>>>` again, substituting `Opaque` into itself even deeper. Eventually this will get to the point that we're just stack-overflowing on a really deep type before even hitting an opaque again.

To fix this, we just bottom out into `ty::Error` instead of the unrevealed opaque type.

Fixes #117412

r? `@oli-obk`

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