drm/panel: Simplify with dev_err_probe()

dev_err_probe() can check if the error code is -EPROBE_DEFER
and can return the error code, replacing dev_err() with it
simplifies the code.
Signed-off-by: Chen Haonan <chen.haonan2@zte.com.cn>
Reviewed-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Link: https://lore.kernel.org/r/3ac20d355b0b3ad3cedb87c8f4efa819a055624b.1702967834.git.chen.haonan2@zte.com.cnSigned-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/3ac20d355b0b3ad3cedb87c8f4efa819a055624b.1702967834.git.chen.haonan2@zte.com.cn

drivers/gpu/drm/panel/panel-boe-himax8279d.c

@@ -854,26 +854,20 @@ static int panel_add(struct panel_info *pinfo)
 
 	pinfo->pp18_gpio = devm_gpiod_get(dev, "pp18", GPIOD_OUT_HIGH);
 	if (IS_ERR(pinfo->pp18_gpio)) {
-		ret = PTR_ERR(pinfo->pp18_gpio);
-		if (ret != -EPROBE_DEFER)
-			dev_err(dev, "failed to get pp18 gpio: %d\n", ret);
-		return ret;
+		return dev_err_probe(dev, PTR_ERR(pinfo->pp18_gpio),
+							 "failed to get pp18 gpio\n");
 	}
 
 	pinfo->pp33_gpio = devm_gpiod_get(dev, "pp33", GPIOD_OUT_HIGH);
 	if (IS_ERR(pinfo->pp33_gpio)) {
-		ret = PTR_ERR(pinfo->pp33_gpio);
-		if (ret != -EPROBE_DEFER)
-			dev_err(dev, "failed to get pp33 gpio: %d\n", ret);
-		return ret;
+		return	dev_err_probe(dev, PTR_ERR(pinfo->pp33_gpio),
+							 "failed to get pp33 gpio\n");
 	}
 
 	pinfo->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_HIGH);
 	if (IS_ERR(pinfo->enable_gpio)) {
-		ret = PTR_ERR(pinfo->enable_gpio);
-		if (ret != -EPROBE_DEFER)
-			dev_err(dev, "failed to get enable gpio: %d\n", ret);
-		return ret;
+		return	dev_err_probe(dev, PTR_ERR(pinfo->enable_gpio),
+						 "failed to get enable gpio\n");
 	}
 
 	drm_panel_init(&pinfo->base, dev, &panel_funcs,