wrong `help: try parenthesizing the first index`

Code:
```rust
pub fn rust_function(x: ((i32, i32), i32)) -> i32 { x.0.0 }
```

Output:
```rust
(...)
help: try parenthesizing the first index
  | pub fn rust_function(x: ((i32, i32), i32)) -> i32 { x.(x.0).0 }
(...)
```

Expected:
```rust
(...)
help: try parenthesizing the first index
  | pub fn rust_function(x: ((i32, i32), i32)) -> i32 { (x.0).0 }
(...)
```