VAAPI: VPP deinterlacing

This adds @btbn work to OpenELEC. We decided to disable the MADI and MACI algorithms by default. They can be enabled via advancedsettings.xml though. They cause problems with especially Haswell. 

Known issue for now: mpeg-2 on haswell is a bit greenish, when being deinterlaced. I will track of those issues, especially when libva-driver-intel 1.2.3 is released.

I currently could only compile test the xbmc changes. Somebody please reviews the libva changes of the unpack script and the patches folder.

The longterm plan until oe 4.0 is to have MADI and MACI working on all platforms.