drm/rockchip: inno_hdmi: Fix video timing

drm/rockchip: inno_hdmi: Fix video timing

The controller wants the difference between *total and *sync_start in the
HDMI_VIDEO_EXT_*DELAY registers. Otherwise the signal is very unstable for
certain non-VIC modes. See downstream commit [0].

[0] https://github.com/rockchip-linux/kernel/commit/8eb559f2502c

Fixes: 412d4ae6b7a5 ("drm/rockchip: hdmi: add Innosilicon HDMI support")
Co-developed-by: Zheng Yang <zhengyang@rock-chips.com>
Signed-off-by: Zheng Yang <zhengyang@rock-chips.com>
Signed-off-by: Alex Bee <knaerzche@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20231222174220.55249-4-knaerzche@gmail.com