net: dm9051: Use PTR_ERR_OR_ZERO() to simplify code

Return PTR_ERR_OR_ZERO() instead of return 0 or PTR_ERR() to
simplify code.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20230817022418.3588831-1-ruanjinjie@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: Ruan Jinjie

drivers/net/ethernet/davicom/dm9051.c

@@ -510,10 +510,7 @@ static int dm9051_map_init(struct spi_device *spi, struct board_info *db)
 
 	regconfigdmbulk.lock_arg = db;
 	db->regmap_dmbulk = devm_regmap_init_spi(db->spidev, &regconfigdmbulk);
-	if (IS_ERR(db->regmap_dmbulk))
-		return PTR_ERR(db->regmap_dmbulk);
-
-	return 0;
+	return PTR_ERR_OR_ZERO(db->regmap_dmbulk);
 }
 
 static int dm9051_map_chipid(struct board_info *db)