media: dt-bindings: Add Intersil ISL79987 DT bindings

Add bindings for the Intersil ISL79987 analog to MIPI CSI-2 decoder.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
To: linux-media@vger.kernel.org
Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>