CRAS: iodev - Tune the ramp duration

Set ramp duration for new stream to 0.01 so user does not miss the
start of new stream.
Set ramp duration for mute to 0.1 so mute can happen sooner.

BUG=chromium:709323
TEST=make check
TEST=check ramp duration for new stream is almost not noticeable.
TEST=check ramp duration for mute is much shorter than before.

Change-Id: If74d094aad11748e3198e8e9402a4d4de9631694
Reviewed-on: https://chromium-review.googlesource.com/472327
Commit-Ready: Cheng-Yi Chiang <cychiang@chromium.org>
Tested-by: Cheng-Yi Chiang <cychiang@chromium.org>
Reviewed-by: Chinyue Chen <chinyue@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>
2 files changed