libaudio: Dock audio support

Currently this routes media to the dock, but keeps call I/O on the
device speaker.

Works with Steven Harper's Samsung dock audio patches from 2-3
months ago.

Change-Id: I41764f51f8c2df4d2f745ebdb8ada1abf0c29848
aries-common: use common recovery.rc

Note that init.recovery.aries.rc is intentionally copied to
root instead of recovery/root, the build system will put it
in the correct place.

Change-Id: Ie8dc0a320c1ceb62e3679c4cfaf39d1553918982
aries-common: fix lun mounting in recovery

without specifying the lun file, the recovery will get confused when
there is no sdcard inserted

Change-Id: Id66c029734671ff1cfb3dedd1e9e3946216e2a8c