Add category for docks and USB devices

 * New category which handles both docks and USB audio devices, since
   USB devices such as DACs still appear as a dock to Android.

Change-Id: I534f6abb95af6325475467fc0ed3cd86be6c058f
Merge branch 'cm-10.2' of git://github.com/CyanogenMod/android_packages_apps_DSPManager into cm-10.2