power: supply: mm8013: Fix error code in mm8013_probe()

The value of ret is zero when passed to dev_error_probe(), we are passing
zero to dev_err_probe() is a success which is incorrect.

Fix this by getting the error code using PTR_ERR().

Fixes: c75f4bf ("power: supply: Introduce MM8013 fuel gauge driver")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202309190838.eu8WS6sz-lkp@intel.com/
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Link: https://lore.kernel.org/r/20230923114807.2829188-1-harshit.m.mogalapalli@oracle.com
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Author: harshimogalapalli

drivers/power/supply/mm8013.c

@@ -273,8 +273,10 @@ static int mm8013_probe(struct i2c_client *client)
 	chip->client = client;
 
 	chip->regmap = devm_regmap_init_i2c(client, &mm8013_regmap_config);
-	if (IS_ERR(chip->regmap))
+	if (IS_ERR(chip->regmap)) {
+		ret = PTR_ERR(chip->regmap);
 		return dev_err_probe(dev, ret, "Couldn't initialize regmap\n");
+	}
 
 	ret = mm8013_checkdevice(chip);
 	if (ret)