clk: sunxi: Add mod0 and mmc module clock support for A80

The module 0 style clocks, or storage module clocks as named in the
official SDK, are almost the same as the module 0 clocks on earlier
Allwinner SoCs. The only difference is wider mux register bits.

As with earlier Allwinner SoCs, mmc module clocks are a special case
of mod0 clocks, with phase controls for 2 child clocks, output and
sample.

This patch adds support for both.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>