ARM: tegra: dvfs: Add alternative dvfs frequency limits

Added an option to specify alternative dvfs frequency limits for each
tegra clock domain. These alternative limits can be applied in some
particularly extreme (e.g., slow) corner of process-temperature space
with no effect on regular limits for the rest of the space.

Bug 913884

Change-Id: I05e319b60f6dc6f4e7f15c7e677e5a3bce77f201
Signed-off-by: Alex Frid <afrid@nvidia.com>
Reviewed-on: http://git-master/r/70188
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com>
Tested-by: Diwakar Tundlam <dtundlam@nvidia.com>
Reviewed-by: Krishna Reddy <vdumpa@nvidia.com>
Reviewed-on: http://git-master/r/75614
Reviewed-by: Varun Wadekar <vwadekar@nvidia.com>
Tested-by: Varun Wadekar <vwadekar@nvidia.com>