clk: rockchip: add clock controller for px30

Add the clock tree definition for the new px30 SoC.
Fix up the pll setting to support px30 SoC.

Change-Id: Ib9255094b0fdb58f0a8ba49c5bb9f075c7458940
Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>

Author: Elaine Zhang