V4L/DVB (11902): pxa-camera: Use v4l bounding/alignment function

The v4l function has a better algorithm for aligning image size.

For instance the old code would change 159x243 into 156x240 to meet the
alignment requirements.  The new function will use 160x243, which is a lot
closer to what was asked for originally.

Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>