[media] Add DT binding documentation for Samsung S5K5BAF camera sensor

This patch adds the DT bindings documentation for Samsung S5K5BAF
Image Sensor.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>