[3.x] Move COREAUDIO_ENABLED check inside AUDIO_DRIVER_COREAUDIO_H block

[halotroop2288]

No description provided.

[halotroop2288]

OK we can do it your way. It's done.

[akien-mga]

Thanks for the contribution!

As I pointed out on #87272 (comment), for the 3.x branch we prefer not to do this kind of style fixes unless they actually solve a problem. It took a lot of effort to improve the code style consistency of the whole codebase in the master branch, and redoing all that work for 3.x wouldn't be worth the effort at this stage.

The change in this commit is correct, but I know there are many other places with similar style inconsistencies which have no incidence on the functionality of the code, as I've fixed them all in the master branch. For this case specifically, you can have a look at #63368. As you can see, more than a thousand lines of code were impacted, so doing it file by file as started in this PR wouldn't be a good option. I wouldn't suggest trying to backport this PR to 3.x, as again this would be more effort than worth (not only to do it, but also for maintainers to review it and make sure there's effectively no change in behavior).

I included this change in #87272 because why not, but otherwise I'd advise against trying to tackle other such minor header guard name/comment inconsistencies if they're not actual bugs that change the code logic.