* wiggle: fix compilation with async functions when tracing is off
Fixes#5202
* switch tracing config from a boolean to a struct
This will enable more complex tracing rules in the future
* rename AsyncConfField to FunctionField
It is going to be reused for cases other than just async functions
* add support for disabling tracing per-function
This adds a `disable_for` syntax after the `tracing` boolean. For
example:
```
wiggle::from_witx!(
tracing: true disable_for {
module1::foo,
module2::{bar, baz},
}
)
```