V4L/DVB: pxa-camera: use memory mapped IO access for camera (QCI) registers

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>