drm/panel: raydium-rm67191: Don't call unprepare+disable at shutdown

drm/panel: raydium-rm67191: Don't call unprepare+disable at shutdown

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. The IMX driver appears to be
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: Robert Chiras <robert.chiras@nxp.com>
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.v3.22.Id14188f1a8af7d524751c27c343a5b583ff5361f@changeid
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240604172305.v3.22.Id14188f1a8af7d524751c27c343a5b583ff5361f@changeid