clk: samsung: exynos5420: Preserve CPU clocks configuration during suspend/resume

clk: samsung: exynos5420: Preserve CPU clocks configuration during suspend/resume

Save and restore top PLL related configuration registers for big (APLL)
and LITTLE (KPLL) cores during suspend/resume cycle. So far, CPU clocks
were reset to default values after suspend/resume cycle and performance
after system resume was affected when performance governor has been selected.

Fixes: 2d4ca3845104 ("clk: samsung: exynos5420: add more registers to restore list")
Signed-off-by: Marian Mihailescu <mihailescu2m@gmail.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>