V4L/DVB (7669): pxa_camera: Add support for YUV modes

This patch adds support for YUV packed and planar capture for pxa_camera.

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>