ASoC: rt1316: Fix return value check in rt1316_sdw_probe()

In case of error, the function devm_regmap_init_sdw() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR().

Fixes: a262057df513 ("ASoC: rt1316: Add RT1316 SDCA vendor-specific driver")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20210303064041.898281-1-weiyongjun1@huawei.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/rt1316-sdw.c

@@ -669,8 +669,8 @@ static int rt1316_sdw_probe(struct sdw_slave *slave,
 
 	/* Regmap Initialization */
 	regmap = devm_regmap_init_sdw(slave, &rt1316_sdw_regmap);
-	if (!regmap)
-		return -EINVAL;
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
 
 	return rt1316_sdw_init(&slave->dev, regmap, slave);
 }