clocksource/drivers/tegra: Rework for compensation of suspend time

Since the clocksource framework has the support for suspend time
compensation. Re-work the driver to use that, so we can reduce the
duplicate code.

Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>