ARM: dts: rockchip: enable init rate for clock

We need to initialize PLL rate and some of bus clock rate while
kernel init, for there is no other module will do that.

Basically on rk3288 we use GPLL for cpu bus, peripheral bus and
most of peripheral clock, CPLL for devices who require 50M/200M
clock rate, leave NPLL behind for special requirement from
display system.

The common-clock-framework will help us to select best source for
child clocks after we init the PLLs propriety.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>