drivers: sensor: ccs811: provide access to sensor results

Expose the entire content of the ALG_RESULT_DATA block to the
application, primarily so the status and error flags can be seen.  With
those available the application has the ability to detect that a stale
result has been provided so sensor_fetch_sample() can return -EAGAIN in
this case instead of -EIO, and it doesn't need to block which is
annoying.

This should also make the sensor usable on older Nordic Thingy:52
devices with outdated CCS811 application firmware that doesn't properly
implement the DATA_READY bit.

Signed-off-by: Peter A. Bigot <pab@pabigot.com>