clk: rockchip: fix incorrect parent for rk3399's {c,g}pll_aclk_perihp_src

There was a typo, swapping 'c' <--> 'g'.

Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>