nvmem: jz4780-efuse: Use PTR_ERR_OR_ZERO() to simplify code

Fixes coccicheck warning:

drivers/nvmem/jz4780-efuse.c:214:1-3: WARNING: PTR_ERR_OR_ZERO can be used
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Samuel Zou <zou_wei@huawei.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200511145042.31223-4-srinivas.kandagatla@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/nvmem/jz4780-efuse.c

@@ -211,10 +211,8 @@ static int jz4780_efuse_probe(struct platform_device *pdev)
 	cfg.priv = efuse;
 
 	nvmem = devm_nvmem_register(dev, &cfg);
-	if (IS_ERR(nvmem))
-		return PTR_ERR(nvmem);
 
-	return 0;
+	return PTR_ERR_OR_ZERO(nvmem);
 }
 
 static const struct of_device_id jz4780_efuse_match[] = {