False positive for use_self when using const generics.

[chanks]

Lint name: use_self

Reproduction using current nightly on Playground

I tried this code:

#![warn(clippy::use_self)]

struct MyStruct<const C: char>;

impl From<MyStruct<'a'>> for MyStruct<'b'> {
    fn from(_s: MyStruct<'a'>) -> Self {
        Self
    }
}

fn main() {}

I expected to see this happen: No clippy warnings.

Instead, this happened:

    Checking playground v0.0.1 (/playground)
warning: unnecessary structure name repetition
 --> src/main.rs:5:11
  |
5 | impl From<MyStruct<'a'>> for MyStruct<'b'> {
  |           ^^^^^^^^^^^^^ help: use the applicable keyword: `Self`
  |
note: the lint level is defined here
 --> src/main.rs:1:9
  |
1 | #![warn(clippy::use_self)]
  |         ^^^^^^^^^^^^^^^^
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#use_self

warning: unnecessary structure name repetition
 --> src/main.rs:6:17
  |
6 |     fn from(_s: MyStruct<'a'>) -> Self {
  |                 ^^^^^^^^^^^^^ help: use the applicable keyword: `Self`
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#use_self

warning: 2 warnings emitted

    Finished dev [unoptimized + debuginfo] target(s) in 0.88s

Using Self in either of the spots indicated changes the meaning of the code.

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Clippy and rustc are current nightly: 2021-05-09

This seems like a very similar error to #7205, but I filed them separately because they're different lints.