[media] saa7134: Add pm_qos_request to fix video corruption

The SAA7134 appears to have trouble buffering more than one line of video
when doing DMA. Rather than try to fix the driver to cope (as has been done
by Andy Walls for the cx18 driver), put in a pm_qos_request to limit deep
sleep exit latencies.
The visible effect of not having this is that seemingly random lines are
only partly transferred - if you feed in a static image, you see a portion
of the image "flicker" into place.

[mchehab@redhat.com: Fix ABI breakage due to some renames at pm_qos]
Signed-off-by: Simon Farnsworth <simon.farnsworth@onelan.co.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>