HID: hid-sensor-custom: Add custom sensor iio support

HID: hid-sensor-custom: Add custom sensor iio support

Currently custom sensors properties are not decoded and it is up to
user space to interpret.

Some manufacturers already standardized the meaning of some custom sensors.
They can be presented as a proper IIO sensor. We can identify these sensors
based on manufacturer and serial number property in the report.

This change is identifying hinge sensor when the manufacturer is "INTEL".
This creates a platform device so that a sensor driver can be loaded to
process these sensors.

Signed-off-by: Ye Xiang <xiang.ye@intel.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Link: https://lore.kernel.org/r/20201215054444.9324-2-xiang.ye@intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>