[Intel-gfx] xf86-video-intel drm-gem branch merged

[Jesse Barnes]

I tracked down the blocker issue today[1], so I went ahead and merged drm-gem 
into master.  Building master now requires a recent libdrm from git, but 
hopefully a real version of that will be released soon.  We could also 
consider adding some conditional code so that it'll build with old libdrms if 
necessary.

GEM won't be used unless the underlying kernel supports it, so there shouldn't 
be any regressions (aside from the already reported bugs QA told me about 
before I merged, but they're not that serious), but please refresh your trees 
and report any problems.

[1] Carl's been making some good changes to the composite code lately, but one 
of them was causing trouble so I reverted it.  We really need to check for 
aperture space after new allocations and before relocations are processed, 
but the way our composite stuff works right now makes that difficult.

Thanks,
Jesse