iio: gyro: bmg160_i2c: Use vsprintf extension %pe for symbolic error name

Utilize %pe format specifier from vsprintf while printing error logs
with dev_err(). Discards the use of unnecessary explicit casting and
prints symbolic error name which might prove to be convenient during
debugging.
Signed-off-by: Nishant Malpani <nish.malpani25@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/gyro/bmg160_i2c.c

@@ -21,8 +21,8 @@ static int bmg160_i2c_probe(struct i2c_client *client,
 
 	regmap = devm_regmap_init_i2c(client, &bmg160_regmap_i2c_conf);
 	if (IS_ERR(regmap)) {
-		dev_err(&client->dev, "Failed to register i2c regmap %d\n",
-			(int)PTR_ERR(regmap));
+		dev_err(&client->dev, "Failed to register i2c regmap: %pe\n",
+			regmap);
 		return PTR_ERR(regmap);
 	}