[mythtv] Updated patch for directshow filters with MythTV (for CoreAVC)

[Alan Nisota]

Andrew Lyon wrote:
> Its working, colours are a bit off but its playing back in realtime!,
> I'm going to upgrade my kernel and nvidia drivers and do more testing,
> ive been meaning to bring them up to date anyway..
The color issue may be due to the output format we're using.  I am using 
I420 because that is what Myth wants, but it may be that YV12 works 
better.  If I can get a sample that shows the problem in myth, I can 
test it in mplayer and see if I can figure out what needs to be done.

Also, I now have multiple CPUs almost working, and it gives a huge 
speedup.  The only problem is that I get a segfault at the end of 
playback (inside the codec).  Once I get that worked out, I'll update 
the patch with the fixes that have come up so far.