[PATCH RFC 3/8] clk: sunxi-ng: a733: Add PRCM CCU

[Enzo Adriano]

Hi Junhui,

Register check for the PRCM driver against the public A733 User Manual
V0.92, chapter 4.2.5: all 41 entries I could extract (13 reset-map
entries, 18 bus gates, 10 mod/mux clocks) match the manual's register
offsets and bit positions. No discrepancies found in this patch.

For what it's worth, we have also exercised the R-domain at runtime on a
Radxa Cubie A7S (r-ahb/r-apb0 rates with live consumers on r-pinctrl,
r-rtc and the PPU, bus-r-cpucfg via its critical flag), with no
misbehavior attributable to the PRCM model.

Thanks,
Enzo