dt-bindings: media: imx335: Add reset-gpios to the DT example

It's easy to get the polarity of GPIOs in the device tree wrong, as
shown by a recently fixed bug in the imx335 driver. To lower the chance
of future mistakes, especially in new bindings that would take the
imx335 binding as a starting point, add the reset-gpios property to the
DT example. This showcases the correct polarity of the XCLR signal for
Sony sensors in the most common case of the signal not being inverted on
the board.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>