drm: renesas: rz-du: Add support for RZ/T2H SoC

drm: renesas: rz-du: Add support for RZ/T2H SoC

The RZ/T2H (R9A09G077) SoC includes a DU with a DPI interface,
supporting resolutions up to WXGA with two RPFs for layer blending.
Unlike earlier RZ/G2L SoCs, RZ/T2H requires explicit assertion of a
DPI output-enable signal (DU_MCR0_DPI_EN) during CRTC startup.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Link: https://patch.msgid.link/20260519160825.4082566-6-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>