Fixes a crash on macOS 15 when using CoreML. (#22277)
### Description
In macOS 15, apps running with CoreML will crash with an error message
like this one:
```
Terminating app due to uncaught exception 'NSGenericException', reason: 'Failed to set compute_device_types_mask E5RT: Cannot provide zero compute device types. (1)'
```
This can be easily seen when building ONNXRuntime from source and
running the unit tests. The fix was suggested in [this bug
report](https://forums.developer.apple.com/forums/thread/757040).
I've ported the change to ONNXRuntime and verified that:
* The issue is resolved in macOS 15 (all unit tests pass).
* The behaviour is unchanged in macOS 14.
### Motivation and Context
This fixes #22275 allowing apps using ONNXRuntime with CoreML to work
normally.
