The current CPU clock is missing the option to change the rate of its
parents, leading to improper rates calculated by cpufreq, and eventually
crashes.

Cc: <stable@vger.kernel.org>
Fixes: 5e737617 ("clk: sunxi-ng: Add sun5i CCU driver")
Reported-by: Kevin Hilman <khilman@baylibre.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>