clk: rockchip: disable unused clocks

The rockchip clock driver use CLK_IGNORE_UNUSED flag to make sure
all the clocks are available like default power on state.
We have implement the clock manage in most of rockchip drivers,
it is time to remove it for power save.
Instead we add CLK_IGNORE_UNUSED for some clock nodes which should
be on during boot or no module driver in kernel will initialize it.

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>