drm: panel: orisetech: improve error handling during probe

Use dev_err_probe() helper as directed by core driver model to handle
driver probe error. Use standard helper defined at drivers/base/core.c
to maintain code consistency.

Inspired by,
commit a787e5400a1ce ("driver core: add device probe log helper")

Signed-off-by: Akhilesh Patil <[e-mail]>
Reviewed-by: Neil Armstrong <[e-mail]>
Signed-off-by: Neil Armstrong <[e-mail]>
Link: https://lore.kernel.org/r/aIJagJ/[e-mail]

drivers/gpu/drm/panel/panel-orisetech-ota5601a.c

···
 	}
 
 	err = drm_panel_of_backlight(&panel->drm_panel);
-	if (err) {
-		if (err != -EPROBE_DEFER)
-			dev_err(dev, "Failed to get backlight handle\n");
-		return err;
-	}
+	if (err)
+		return dev_err_probe(dev, err, "Failed to get backlight handle\n");
 
 	drm_panel_add(&panel->drm_panel);