[media] MX2: Add platform definitions for eMMa-PrP device

eMMa-PrP device included in Freescale i.MX2 chips can also
be used separately to process memory buffers. This patch
provides arch glue code for the driver which provides this
functionality.

Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Javier Martin <javier.martin@vista-silicon.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>