clocksource/drivers/tegra: Restore timer rate on Tegra210

The clocksource rate is initialized only for the first per-CPU clocksource
and then that rate shall be replicated for the rest of clocksource's
because they are initialized manually in the code.

Fixes: 3be2a85a0b61 ("clocksource/drivers/tegra: Support per-CPU timers on all Tegra's")
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>