dt-bindings: reset: renesas,rst: Document r8a779g0 reset module

Document bindings for the R-Car V4H (R8A779G0) reset module.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220420084255.375700-4-yoshihiro.shimoda.uh@renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>