arm: tegra: soctherm: add interrupt threshold and filtering

arm: tegra: soctherm: add interrupt threshold and filtering

This patch makes OC_ALARM_*_CNT_THRESHOLD and OC_ALARM_*_FILTER
registers configurable from soc_therm platform data.

Also fix naming of ALARM_THRESHOLD_PERIOD to ALARM_THROTTLE_PERIOD as
per register description.

Bug 1444676

Change-Id: I2901e5cd0ccd893aabbf622169e20b90b5977ff7
Signed-off-by: Timo Alho <talho@nvidia.com>
(cherry picked from commit 81e6acf47d4493eea8f615f89a1cc23279037603)
Reviewed-on: http://git-master/r/359396
Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>