Misleading QML audioDevice.mode enum documentation.

Documentation states that possible values for the device type enum are:

• audioDevice.Null
• audioDevice.Input
• audioDevice.Output

However, using these in QML code causes a runtime error:
`ReferenceError: audioDevice is not defined`

The correct enum values should be:

• AudioDevice.Null
• AudioDevice.Input
• AudioDevice.Output

This is misleading and will inevitably lead to errors when following the documentation.