google/chell: Adjust nuvoton 8825 button thresholds again.

Changing these thresholds again for new tuning in March of 2016.
Something's changed in the latest firmware to cause all
values previously read on Chell to float down.

Set "nuvoton,sar-threshold" property to thresholds
based on tuning with the Android Wired Headphone
Compatibility Kit and Chell DVT.

Signed-off-by: Benson Leung <bleung@chromium.org>

BUG=chrome-os-partner:49333
BRANCH=none
TEST=Run evtest, selecting the input event for sklnau8825adi
Using the Nominal headphones from the kit, check that the
buttons for "KEY_VOLUMEDOWN", "KEY_VOLUMEUP", "KEY_MEDIA",
and code 582 (?) (should be voice search, but evtest doesn't understand)
All of these buttons should work properly.

Change-Id: I11de7a0853a3598f3834e8bae3140b9942cbd0b0
Reviewed-on: https://chromium-review.googlesource.com/334402
Commit-Ready: Benson Leung <bleung@chromium.org>
Tested-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
1 file changed