Voice chat menu option improvements
A few minor improvements have been made to the voice chat options menu:
- The list of record drivers in the menu updates when any drivers are plugged or unplugged.
- A microphone test now stops when the selected record driver isn't recording (e.g. when it's unplugged). If the test bar item is also still selected and there's no more record drivers available, then it's automatically deselected since it isn't selectable anymore.
- The microphone test bar is now greyed out while it isn't selectable.