V4L/DVB: Deprecate cpia driver (used for parallel port webcams)

cpia driver were re-written inside gspca driver, for USB devices. The only
functionality that were not migrated is the support for parallel port,
as:
	1) the developer didn't find any hardware;
	2) it doesn't  seem important to keep support for a parallel port webcam,
	   as this is an obsolete technology;
	3) the changes at gspca for it to work with parallel port would be very large;
	4) this driver still uses BKL.

So, let's move it to drivers/staging and label it to die at 2.6.38, if nobody
cares enough to port parallel port support to gspca or to create a new driver
that uses the same gspca-cpia sub-driver.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>