- refactor ddi buffer programming a bit (Ville)

- large-scale renaming to untangle naming in the gem code (Chris)
- rework vma/active tracking for accurately reaping idle mappings of shared
  objects (Chris)
- misc dp sst/mst probing corner case fixes (Ville)
- tons of cleanup&tunings all around in gem
- lockless (rcu-protected) request lookup, plus use it everywhere for
  non(b)locking waits (Chris)
- pipe crc debugfs fixes (Rodrigo)
- random fixes all over