drm: xlnx: zynqmp: Fix max dma segment size

[ Upstream commit 28b529a9 ]

Fix "mapping sg segment longer than device claims to support" warning by
setting the max segment size.

Fixes: d76271d2 ("drm: xlnx: DRM/KMS driver for Xilinx ZynqMP DisplayPort Subsystem")
Reviewed-by: Sean Anderson <sean.anderson@linux.dev>
Tested-by: Sean Anderson <sean.anderson@linux.dev>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250115-xilinx-formats-v2-10-160327ca652a@ideasonboard.com


Signed-off-by: Sasha Levin <sashal@kernel.org>