iio: adc: adi-axi-adc: only error out in major version mismatch

iio: adc: adi-axi-adc: only error out in major version mismatch

The IP core only has breaking changes when there major version changes.
Hence, only match the major number. This is also in line with the other
core ADI has upstream. The current check for erroring out
'expected_version > current_version"' is then wrong as we could just
increase the core major with breaking changes and that would go
unnoticed.

Fixes: ef04070692a2 ("iio: adc: adi-axi-adc: add support for AXI ADC IP core")
Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240419-ad9467-new-features-v1-2-3e7628ff6d5e@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>