drm/panel: boe-tv101wum-nl6: Don't call unprepare+disable at shutdown/remove

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 Mediatek and Qualcomm boards. Both of
those drivers appear 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: Jitao Shi <jitao.shi@mediatek.com>
Cc: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240503143327.RFT.v2.5.I5bd120aa0b7d17a1149ea43cc4852492834058c0@changeid

drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c

@@ -1833,21 +1833,11 @@ static int boe_panel_probe(struct mipi_dsi_device *dsi)
 	return ret;
 }
 
-static void boe_panel_shutdown(struct mipi_dsi_device *dsi)
-{
-	struct boe_panel *boe = mipi_dsi_get_drvdata(dsi);
-
-	drm_panel_disable(&boe->base);
-	drm_panel_unprepare(&boe->base);
-}
-
 static void boe_panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct boe_panel *boe = mipi_dsi_get_drvdata(dsi);
 	int ret;
 
-	boe_panel_shutdown(dsi);
-
 	ret = mipi_dsi_detach(dsi);
 	if (ret < 0)
 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", ret);
@@ -1892,7 +1882,6 @@ static struct mipi_dsi_driver boe_panel_driver = {
 	},
 	.probe = boe_panel_probe,
 	.remove = boe_panel_remove,
-	.shutdown = boe_panel_shutdown,
 };
 module_mipi_dsi_driver(boe_panel_driver);