iio: light: apds9306: Fix off by one in apds9306_sampling_freq_get()

The > comparison needs to be >= to prevent an out of bounds access.

Fixes: 620d1e6c ("iio: light: Add support for APDS9306 Light Sensor")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Subhajit Ghosh <subhajit.ghosh@tweaklogic.com>
Link: https://lore.kernel.org/r/69c5cb83-0209-40ff-a276-a0ae5e81c528@moroto.mountain


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>