[media] vp702x: comment dead code

Since the first version of this driver, the remote controller
code is disabled, adding an early return inside vp702x_rc_query().

Let's disable the code with #if 0, to remove this warning:

drivers/media/usb/dvb-usb/vp702x.c:268 vp702x_rc_query() info: ignoring unreachable code.

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