clk: composite: support determine_rate using rate_ops->round_rate + mux_ops->set_parent

In case the rate_hw does not implement determine_rate, but only round_rate
we fallback to best_parent selection if mux_hw is present and support
reparenting.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
clk-pll: we only need clk-provider.h not clk-private.h
pinctrl-rockchip: convert output back to debug again
clk: rockchip: add composite type
clk: rk3188: convert some initial clocks to composite type