iio: light: st_uvis25: Drop unneeded casting when print error code

Explicit casting in printf() usually shows that something is not okay.
Here, we really don't need it by providing correct specifier.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>