clk: samsung: Add support to register rate_table for samsung plls

This patch defines a common rate_table which will contain recommended p, m, s,
k values for supported rates that needs to be changed for changing
corresponding PLL's rate.

Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>