iio: adc: MCP3564: fix hardware identification logic

iio: adc: MCP3564: fix hardware identification logic

In mcp3564_config() fix the hardware identification logic
based on the hardware ID registers. Second part of the code was
disabled by an logic error.
Fix a typo related to the "MODULE_DESCRIPTION".

Fixes: 33ec3e5fc1ea (iio: adc: adding support for MCP3564 ADC)
Signed-off-by: Marius Cristea <marius.cristea@microchip.com>
Link: https://lore.kernel.org/r/20231129135619.63475-1-marius.cristea@microchip.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>