Revert "Add support for USB audio docks."

Revert submission 16691170-usb_doc

Reason for revert: 216248574
Reverted Changes:
I090e86b2e:Add support for USB audio docks.
I461661dd4:audio policy: implement routing policy for USB doc...

Change-Id: Ie28b74de7b8654cd199c86d06697bb52f0fa8f3d
5 files changed