clk: sunxi: Rework clock protection code

Since we start to have a lot of clocks to protect, some of them in a
few SoCs only, it becomes difficult to handle the clock protection
without having to add per machine exceptions.

Add per-SoC data to tell which clock to leave enabled.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Emilio López <emilio@elopez.com.ar>