drm/panel: ili9881c: Make use of the helper function dev_err_probe()

When possible use dev_err_probe help to properly deal with the
PROBE_DEFER error, the benefit is that DEFER issue will be logged
in the devices_deferred debugfs file.
And using dev_err_probe() can reduce code size, and the error value
gets printed.
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210916104240.11217-1-caihuoqing@baidu.com

drivers/gpu/drm/panel/panel-ilitek-ili9881c.c

@@ -653,16 +653,14 @@ static int ili9881c_dsi_probe(struct mipi_dsi_device *dsi)
 		       DRM_MODE_CONNECTOR_DSI);
 
 	ctx->power = devm_regulator_get(&dsi->dev, "power");
-	if (IS_ERR(ctx->power)) {
-		dev_err(&dsi->dev, "Couldn't get our power regulator\n");
-		return PTR_ERR(ctx->power);
-	}
+	if (IS_ERR(ctx->power))
+		return dev_err_probe(&dsi->dev, PTR_ERR(ctx->power),
+				     "Couldn't get our power regulator\n");
 
 	ctx->reset = devm_gpiod_get(&dsi->dev, "reset", GPIOD_OUT_LOW);
-	if (IS_ERR(ctx->reset)) {
-		dev_err(&dsi->dev, "Couldn't get our reset GPIO\n");
-		return PTR_ERR(ctx->reset);
-	}
+	if (IS_ERR(ctx->reset))
+		return dev_err_probe(&dsi->dev, PTR_ERR(ctx->reset),
+				     "Couldn't get our reset GPIO\n");
 
 	ret = drm_panel_of_backlight(&ctx->panel);
 	if (ret)