device: Add mixer_paths and update audio_policy

Also delete the old snd_soc_msm files - they don't
do anything with the new audio HAL
Change-Id: Iaf7d8fc5d63f0bd81b7f88ee6051b20804825e69
init: Change sdcard emulation mode

WHAT THE HECK?  Why does this device have split storage
where the internal sdcard is formatted ext4?

If you're going finally kill UMS (ext4 will do it), WHY
use split storage?

Change-Id: I39542aabf44b2653588859a48d7ae4e5bc88a461