staging: iio: light: iqs253: Fine tune settings

staging: iio: light: iqs253: Fine tune settings

- Channel 0 to be used for stylus detection
- Channel 1 and 2 to be used for proximity detection
- Channel 0 should detect proximity at 0.5 cm
- Channel 1 and 2 should detect proximity at 2 cm
- SAR gpio to be pulled high on proximity detection else high

Change-Id: I5a706583a9bace6b740f319cf7264db79857993c
Signed-off-by: Sri Krishna chowdary <schowdary@nvidia.com>
Reviewed-on: http://git-master/r/364277
(cherry picked from commit 0dac45f0d954c8d134fd0204f8f7c9999d98dd9f)
Reviewed-on: http://git-master/r/368240
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Sachin Nikam <snikam@nvidia.com>