It's the responsibility of a correctly written DRM modeset driver to
call drm_atomic_helper_shutdown() at shutdown time and that should be
disabling / unpreparing the panel if needed. Panel drivers shouldn't
be calling these functions themselves.

A recent effort was made to fix as many DRM modeset drivers as
possible [1] [2] [3] and most drivers are fixed now.

A grep through mainline for compatible strings used by this driver
indicates that it is used by IMX boards. As far as I can tell, all IMX
boards are now correctly calling drm_atomic_helper_shutdown() so we
can remove the calls.

[1] https://lore.kernel.org/r/20230901234015.566018-1-dianders@chromium.org
[2] https://lore.kernel.org/r/20230901234202.566951-1-dianders@chromium.org
[3] https://lore.kernel.org/r/20230921192749.1542462-1-dianders@chromium.org

Cc: Marco Franchi <marco.franchi@nxp.com>
Cc: Fabio Estevam <festevam@denx.de>
Cc: Laurentiu Palcu <laurentiu.palcu@oss.nxp.com>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: imx@lists.linux.dev
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20240604172305.v3.16.Ief712fb6720cb98bdf9ec8644362d028b6554f9b@changeidSigned-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240604172305.v3.16.Ief712fb6720cb98bdf9ec8644362d028b6554f9b@changeid