(PhAudio) Fix device selection when name contains accents

Dear Joker developers,

On a french Windows machine, when the name of audio devices contain accents, Joker fails to select these devices:

![bug_accents_in_audio_devices_names](https://cloud.githubusercontent.com/assets/44706/3496789/1f912008-05e6-11e4-9f61-0999578e2348.png)

The following commit fixes the encoding mismatch that is causing this situation.

Best regards.