V4L/DVB: v4l: Add driver for Samsung S5P SoC video postprocessor

This driver exports a video device node per each camera interface/
video postprocessor (FIMC) device contained in Samsung S5P SoC series.
The driver is based on v4l2-mem2mem framework.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Pawel Osciak <p.osciak@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>