iio: adc: ad7124: fix division by zero in ad7124_set_channel_odr()

In the Linux kernel, the following vulnerability has been resolved: iio: adc: ad7124: fix division by zero in ad7124_set_channel_odr() In the ad7124_write_raw() function, parameter val can potentially be zero. This may lead to a division by zero when DIV_ROUND_CLOSEST() is called within ad7124_set_channel_odr(). The ad7124_write_raw() function is invoked through the sequence: iio_write_channel_raw() -> iio_write_channel_attribute() -> iio_channel_write(), with no checks in place to ensure val is non-zero.