i2c/writing-clients: Fix foo_driver.id_table

The i2c_device_id structure variable's name is not used in the
i2c_driver structure.
Signed-off-by: Vikram Narayanan <vikram186@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Jean Delvare <khali@linux-fr.org>

Documentation/i2c/writing-clients

@@ -38,7 +38,7 @@ static struct i2c_driver foo_driver = {
 		.name	= "foo",
 	},
 
-	.id_table	= foo_ids,
+	.id_table	= foo_idtable,
 	.probe		= foo_probe,
 	.remove		= foo_remove,
 	/* if device autodetection is needed: */