ARM: tegra: clock: Support variable iso share calculator

ARM: tegra: clock: Support variable iso share calculator

Added and option to calculate iso share for each use case based on
iso bw (instead of fixed share across entire bw range).

Bug 1259082

Change-Id: Ic995e445bd2daa6e02b0b247ca01ddb3d72196b1
Signed-off-by: Alex Frid <afrid@nvidia.com>
Signed-off-by: Daniel Solomon <daniels@nvidia.com>
(cherry picked from commit 627bc12f845b52e49b26e0cda0ba32d44e974399)
Reviewed-on: http://git-master/r/252580
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Krishna Reddy <vdumpa@nvidia.com>