rustdoc: Many times the same `From<!> for T` impl for the `!` type

[poliorcetics]

https://doc.rust-lang.org/nightly/std/primitive.never.html#blanket-implementations

All pointing to the same impl:

@rustbot label +T-rustdoc

[fmease]

Actually, the never type !, the trait From and #[rustc_reservation_impl] are not needed: It occurs with any type and any parameterized trait.
Minimal reproducible example:

#![crate_type = "lib"]

impl<T> Something<Whatever> for T { }    // blanket impl is duplicated on Whatever's page
pub struct Whatever { /* whatever */ }

pub trait Something<T> { }

The number of duplicates depends on the number of public types accessible in the target crate.

[GuillaumeGomez]

Taking a look.

[GuillaumeGomez]

@fmease's code:

pub trait Something<T> { }
pub struct Whatever;
impl<T> Something<Whatever> for T {}

Gives: