Accelerometer: Get scale from sensors with IIO_SHARED_BY_ALL mask.
Created by: danielstuart14
Properties with IIO_SHARED_BY_ALL mask don't have the sensor type prefix before the file identifier, this caused some devices to not use the scale from sysfs.
As so, it is fixed by searching through sysfs for both properties: scale and in_accel_scale.
This commit is based on f14d26d1 [accel-location: add helper functions for ACCEL_LOCATION udev property].