iio:dac: drop assignment of iio_info.driver_module

The equivalent of this is now done via macro magic when
the relevant register call is made.  The actual structure
element will shortly go away.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>

drivers/iio/dac/mcp4922.c

@@ -119,7 +119,6 @@ static const struct iio_chan_spec mcp4922_channels[3][MCP4922_NUM_CHANNELS] = {
 static const struct iio_info mcp4922_info = {
 	.read_raw = &mcp4922_read_raw,
 	.write_raw = &mcp4922_write_raw,
-	.driver_module = THIS_MODULE,
 };
 
 static int mcp4922_probe(struct spi_device *spi)