CRAS: fmt_conv - Only apply channel remix for S16_LE

On some USB device that supports 24 bits audio, enabling
output channel remix will turn sound into noise. Skip it
until we support 24 bits sample ops.

BUG=b:130203863
TEST=Apply patch, test Salomon dock with accessibility option
'Play the same audio through all speakers' turn on. Verify
output is not noise.

Change-Id: I56803a2be3dc40578c96c14a66574dc06aae1304
Reviewed-on: https://chromium-review.googlesource.com/1630419
Commit-Ready: Hsinyu Chao <hychao@chromium.org>
Tested-by: Hsinyu Chao <hychao@chromium.org>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Hsinyu Chao <hychao@chromium.org>
2 files changed