nouveau regression fixes, and some minor fixes.

* 'linux-4.15' of git://github.com/skeggsb/linux:
  drm/nouveau: use alternate memory type for system-memory buffers with kind != 0
  drm/nouveau: avoid GPU page sizes > PAGE_SIZE for buffer objects in host memory
  drm/nouveau/mmu/gp10b: use correct implementation
  drm/nouveau/pci: do a msi rearm on init
  drm/nouveau/imem/nv50: fix refcount_t warning
  drm/nouveau/bios/dp: support DP Info Table 2.0
  drm/nouveau/fbcon: fix NULL pointer access in nouveau_fbcon_destroy