Fix await suggestion on non-future type
Remove a match block that would suggest to add `.await` in the case where the expected type's `Future::Output` equals the found type. We only want to suggest `.await`ing in the opposite case (the found type's `Future::Output` equals the expected type).
The code sample is here: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=6ba6b83d4dddda263553b79dca9f6bcb
Before:
```
➜ ~ rustc --edition=2021 --crate-type=lib test.rs
error[E0308]: `match` arms have incompatible types
--> test.rs:4:14
|
2 | let x = match 1 {
| _____________-
3 | | 1 => other(),
| | ------- this is found to be of type `impl Future`
4 | | 2 => other().await,
| | ^^^^^^^^^^^^^ expected opaque type, found enum `Result`
5 | | };
| |_____- `match` arms have incompatible types
|
= note: expected type `impl Future`
found enum `Result<(), ()>`
help: consider `await`ing on the `Future`
|
4 | 2 => other().await.await,
| ++++++
error: aborting due to previous error
For more information about this error, try `rustc --explain E0308`.
```
After:
```
➜ ~ rustc +stage1 --edition=2021 --crate-type=lib test.rs
error[E0308]: `match` arms have incompatible types
--> test.rs:4:14
|
2 | let x = match 1 {
| _____________-
3 | | 1 => other(),
| | ------- this is found to be of type `impl Future`
4 | | 2 => other().await,
| | ^^^^^^^^^^^^^ expected opaque type, found enum `Result`
5 | | };
| |_____- `match` arms have incompatible types
|
= note: expected type `impl Future`
found enum `Result<(), ()>`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0308`.
```
Fixes#90931
eb9859f00d