i2c: Fix return value check in i2c-dev

device_create() returns error code as pointer on failures.
This patch checks the return value of device_create() by using IS_ERR().

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index cf9381e..909428a 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -416,8 +416,8 @@
 	i2c_dev->dev = device_create(i2c_dev_class, &adap->dev,
 				     MKDEV(I2C_MAJOR, adap->nr),
 				     "i2c-%d", adap->nr);
-	if (!i2c_dev->dev) {
-		res = -ENODEV;
+	if (IS_ERR(i2c_dev->dev)) {
+		res = PTR_ERR(i2c_dev->dev);
 		goto error;
 	}
 	res = device_create_file(i2c_dev->dev, &dev_attr_name);