Additional incorrect clashing_extern_decl warning for #[repr(transparent)] non-zero types

[jumbatm]

It seems that there is a case still not being fixed, when #[repr(transparent)] is used with non-zero types.

mod a {
    use std::num::NonZeroUsize;
    extern "C" {
        fn a() -> NonZeroUsize;
    }
}

mod b {
    #[repr(transparent)]
    struct X(NonZeroUsize);
    use std::num::NonZeroUsize;
    extern "C" {
        fn a() -> X;
    }
}

Originally posted by @nbdd0121 in #73735 (comment)

[jumbatm]

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