Merge branch 'vmwgfx-fixes-4.16' of git://people.freedesktop.org/~thomash/linux into drm-fixes

Two vmwgfx fixes for 4.16. Both cc'd stable.

* 'vmwgfx-fixes-4.16' of git://people.freedesktop.org/~thomash/linux:
  drm/vmwgfx: Fix a destoy-while-held mutex problem.
  drm/vmwgfx: Fix black screen and device errors when running without fbdev