clk: tegra: add suspend/resume function for tegra_cpu_car_ops

Adding suspend/resume function for tegra_cpu_car_ops. We only save and
restore the setting of the clock of CoreSight. Other clocks still need
to be taken care by clock driver.

Cc: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>