Backmerge of drm-next to resolve a few ugly conflicts and to get a few
fixes from 3.4-rc6 (which drm-next has already merged). Note that this
merge also restricts the stencil cache lra evict policy workaround to
snb (as it should) - I had to frob the code anyway because the
CM0_MASK_SHIFT define died in the masked bit cleanups.

We need the backmerge to get Paulo Zanoni's infoframe regression fix
for gm45 - further bugfixes from him touch the same area and would
needlessly conflict.
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>