net: mtk_eth: simplify the mediatek code return expression

Simplify the return expression at mtk_eth_path.c file, simplify this all.
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Link: https://lore.kernel.org/r/20201211083801.1632-1-zhengyongjun3@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mediatek/mtk_eth_path.c

@@ -252,7 +252,7 @@ int mtk_gmac_sgmii_path_setup(struct mtk_eth *eth, int mac_id)
 
 int mtk_gmac_gephy_path_setup(struct mtk_eth *eth, int mac_id)
 {
-	int err, path = 0;
+	int path = 0;
 
 	if (mac_id == 1)
 		path = MTK_ETH_PATH_GMAC2_GEPHY;
@@ -261,25 +261,17 @@ int mtk_gmac_gephy_path_setup(struct mtk_eth *eth, int mac_id)
 		return -EINVAL;
 
 	/* Setup proper MUXes along the path */
-	err = mtk_eth_mux_setup(eth, path);
-	if (err)
-		return err;
-
-	return 0;
+	return mtk_eth_mux_setup(eth, path);
 }
 
 int mtk_gmac_rgmii_path_setup(struct mtk_eth *eth, int mac_id)
 {
-	int err, path;
+	int path;
 
 	path = (mac_id == 0) ?  MTK_ETH_PATH_GMAC1_RGMII :
 				MTK_ETH_PATH_GMAC2_RGMII;
 
 	/* Setup proper MUXes along the path */
-	err = mtk_eth_mux_setup(eth, path);
-	if (err)
-		return err;
-
-	return 0;
+	return mtk_eth_mux_setup(eth, path);
 }