media: i2c: Add note to prevent buggy code re-use

media: i2c: Add note to prevent buggy code re-use

adv7604 and et8ek8 sensor drivers have mixed up logical and line level
for reset/powerdown signal.  They call it a reset signal (it indeed
behaves like that), but drivers assert the reset to operate which is
clearly incorrect and relies on wrong ACTIVE_HIGH flag in the DTS.

People in discussions copy existing poor code and claim they can repeat
same mistake, so add a note to prevent that.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>