clk: rockchip: add 400MHz and 500MHz for rk3288 clock rate

This patch add 400MHz and 500MHz to clock rate table for rk3288.

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>