clk: sunxi: add compatible string for V3

A new compatible string is introduced for V3 CCU, because it has a few
extra features available.

Add the compatible string to the clock driver. As the extra features are
not touched, just share the description struct now.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>