msm8974: Remove deprecated flags

 * Use Google's new USB audio implementation
 * Remove unnecessary flags

Change-Id: Id2f8dfdecc979b6551625a17732484fb668c8f98
msm8974: Don't build proprietary features

 * Not shipping on this device.

Change-Id: I5332ca9548587c3164cc16f67bca28e11a733f22
msm8974: Enable multiuser

Change-Id: I73ae4efbbf0be8ddb8dadf1aa0850b73825b8002
msm8974: Update blob list

 * NON FINAL

Change-Id: I3f26c0eea888766d59b946d6df42823ff5518eb2