interp/validity: enforce Scalar::Initialized This is a follow-up to https://github.com/rust-lang/rust/pull/94527, to also account for the new kind of `Scalar` layout inside the validity checker. r? `@oli-obk`
interp/validity: enforce Scalar::Initialized This is a follow-up to https://github.com/rust-lang/rust/pull/94527, to also account for the new kind of `Scalar` layout inside the validity checker. r? `@oli-obk`