[media] hdpvr: fix interrupted recording

[media] hdpvr: fix interrupted recording

This is a reworking of a patch originally submitted by Ryley Angus,
modified by Hans Verkuil and then seemingly forgotten before changes
suggested by Keith Pyle here:

http://www.mail-archive.com/linux-media@vger.kernel.org/msg75163.html

were made and tested.

I have implemented the suggested changes and have been testing for the
last 2 months. I am no longer experiencing lockups while recording
(with blue light on, requiring power cycling) which had been a long
standing problem with the HD-PVR. I have not noticed any other problems
since applying the patch.

Signed-off-by: Jonathan Sims <jonathan.625266@earthlink.net>
Reported-by: Ryley Angus <ryleyjangus@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>