arm: tegra12: soctherm: fix throttling depth config

arm: tegra12: soctherm: fix throttling depth config

This patch allows configuring throttling parameters in a way that any
of following register settings can be set to zero:
 * dividend
 * divisor
 * duration
 * step

Change-Id: I77ee5e09a8d0f2b7a47fee33515b431c9b58dae1
Signed-off-by: Timo Alho <talho@nvidia.com>
Reviewed-on: http://git-master/r/361072
(cherry picked from commit 41bdc27fa72b6773e6dace0eaf0118c11823ac73)
Reviewed-on: http://git-master/r/361952
Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>
Tested-by: Juha Tukkinen <jtukkinen@nvidia.com>