[media] go7007: add motion detection support

This patch adds motion detection support to the go7007 driver using the new
motion detection controls, events.

The global motion detection works fine, but the regional motion detection
support probably needs more work. There seems to be some interaction between
regions that makes setting correct thresholds difficult. The exact meaning of
the thresholds isn't entirely clear either.

I do not have any documentation, the only information I have is the custom code
in the driver and a modet.c application.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>