arm64: dts: allwinner: h6: Use macros for R_CCU clock and reset indices

Now that the device tree binding headers for the R_CCU have been merged,
we can use the macros, instead of raw numbers.

Switch to R_CCU macros for clock and reset indices.

Reviewed-by: Icenowy Zheng <icenowy@aosc.io>
Tested-by: Icenowy Zheng <icenowy@aosc.io>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>