Rollup merge of #41062 - estebank:private-field, r=arielb1

Do not recommend private fields called as method

```rust
error: no method named `dog_age` found for type `animal::Dog` in the current scope
  --> $DIR/private-field.rs:26:23
   |
26 |     let dog_age = dog.dog_age();
   |                       ^^^^^^^ private field, not a method
```
Fix #27654.