initial crocus driver submission
This is the initial crocus driver submission MR. It contains a pretty fully functional gallium driver for Intel gen4->gen7 (965->haswell).
There are bunch of precursor patches that need looking at and possible splitting into their own MRs (!11125 (merged) !11098 (merged) !11097 (merged)) (some already have been done), and there are some interactions with some other MRs (like !11145 (merged)) that I need to stay on top off.
At this point I'm mostly here to make sure it builds in CI fine.