dt-bindings: phy: renesas,usb2-phy: Add RZ/T2H and RZ/N2H support

Document the USB2 PHY controller for the Renesas RZ/T2H (r9a09g077) and
RZ/N2H (r9a09g087) SoCs. These SoCs share the same PHY block, which is
similar to the one on RZ/G2L but differs in clocks, resets, and register
bits. To account for these differences, a new compatible string
`renesas,usb2-phy-r9a09g077` is introduced.

The RZ/N2H SoC uses the same PHY as RZ/T2H, so it reuses the RZ/T2H
compatible string as a fallback.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20250808215209.3692744-2-prabhakar.mahadev-lad.rj@bp.renesas.com


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