iio:dac:mcp4725: Suppress clang W=1 warning about pointer to enum conversion.

Cast to a uintptr_t rather than directly to the enum.

As per the discussion in below linked media patch.

Link: https://lore.kernel.org/linux-media/CAK8P3a2ez6nEw4d+Mqa3XXAz0RFTZHunqqRj6sCt7Y_Eqqs0rw@mail.gmail.com/Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20211128172445.2616166-7-jic23@kernel.org

drivers/iio/dac/mcp4725.c

@@ -386,7 +386,7 @@ static int mcp4725_probe(struct i2c_client *client,
 	i2c_set_clientdata(client, indio_dev);
 	data->client = client;
 	if (dev_fwnode(&client->dev))
-		data->id = (enum chip_id)device_get_match_data(&client->dev);
+		data->id = (uintptr_t)device_get_match_data(&client->dev);
 	else
 		data->id = id->driver_data;
 	pdata = dev_get_platdata(&client->dev);