drm: bridge: icn6211: Set SYS_CTRL_1 to value used in examples

drm: bridge: icn6211: Set SYS_CTRL_1 to value used in examples

Both example code [1], [2] as well as one provided by custom panel vendor
set register SYS_CTRL_1 to 0x88. What exactly does the value mean is unknown
due to unavailable datasheet. Align this register value with example code.

[1] https://github.com/rockchip-linux/kernel/blob/develop-4.19/drivers/gpu/drm/bridge/icn6211.c
[2] https://github.com/tdjastrzebski/ICN6211-Configurator

Acked-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
To: dri-devel@lists.freedesktop.org
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220331150509.9838-8-marex@denx.de