[Mlir-commits] [mlir] [mlir][openacc] Switch * to `star` which is more MLIR friendly (PR #74662)

[Valentin Clement バレンタイン クレメン]

clementval wrote:

> LGTM, but you may consider using `all` instead of `star`.

I was hesitant to use `all` because it actually doesn't apply to all the device_type but all that are not defined. 

Like in this example from the standard below, `num_gangs(2)` does not apply to foo and bar. 

> The directive below is the same as the previous directive except that num_gangs(2) has moved after device_type(*) and so now does not apply to foo or bar.
````
!$acc parallel device_type(*) num_gangs(2) &
!$acc device_type(foo) num_gangs(4)  &
!$acc device_type(bar) num_workers(8)
```

https://github.com/llvm/llvm-project/pull/74662