iio: magn: hmc5843: Drop excessive indentation of assignments of hmc5843_driver

This formatting is odd, so fix it to be more standard.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220807184534.1037363-2-jic23@kernel.org