dmaengine: sh: rz-dmac: Add RZ/V2H(P) support

The DMAC IP found on the Renesas RZ/V2H(P) family of SoCs is
similar to the version found on the Renesas RZ/G2L family of
SoCs, but there are some differences:
* It only uses one register area
* It only uses one clock
* It only uses one reset
* Instead of using MID/IRD it uses REQ No
* It is connected to the Interrupt Control Unit (ICU)
* On the RZ/G2L there is only 1 DMAC, on the RZ/V2H(P) there are 5

Add specific support for the Renesas RZ/V2H(P) family of SoC by
tackling the aforementioned differences.

Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20250423143422.3747702-6-fabrizio.castro.jz@renesas.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>