clk: tegra: Save/restore CCLKG_BURST_POLICY on suspend

Save and restore this register since the LP1 restore assembly routines
fiddle with it. Otherwise the CPU would keep running on PLLX after
resume from suspend even when DFLL was the original clocksource.

Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>