[media] videodev2.h: go back to limited range Y'CbCr for SRGB and, ADOBERGB

This reverts 'commit 7e0739cd ("[media] videodev2.h: fix
sYCC/AdobeYCC default quantization range").

The problem is that many drivers can convert R'G'B' content (often
from sensors) to Y'CbCr, but they all produce limited range Y'CbCr.

To stay backwards compatible the default quantization range for
sRGB and AdobeRGB Y'CbCr encoding should be limited range, not full
range, even though the corresponding standards specify full range.

Update the V4L2_MAP_QUANTIZATION_DEFAULT define accordingly and
also update the documentation.

Fixes: 7e0739cd ("[media] videodev2.h: fix sYCC/AdobeYCC default quantization range")
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: <stable@vger.kernel.org>      # for v4.9 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>