m7: Add digital dock routes for LPA and tunnel

 * For supporting music playback over USB.

Change-Id: I07ab7297a7b35b616b02bb775aaa6a2b6dccb331
m7-common: add LPA USB Proxy use case

Change-Id: I979d6ca58ace85bc30a05553705ddae25caadb72
Merge branch 'cm-10.2' into martincz