[Mesa-dev] auxiliary/vl and st/vdpau, xvmc trivial fixes and cleanups v2

[Emil Velikov]

Diff to previous version
patch 1,3,4,5,7 - annotate patches with Reviewed-by tags
patch 2 - rework completely as per Christian's comments
patch 6 - resolve merge conflicts on top of master

Patches are also available at guthub for those interested
https://github.com/evelikov/Mesa/commits/vl-cleanups-v2

Cheers,
Emil