drm/nve0/fb/gddr5: not all memory partitions are created equal

As seen when comparing us vs nv on my GTX660.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --cc drivers/gpu/drm/nouveau/core/include/subdev/fb.h
Simple merge

diff --cc drivers/gpu/drm/nouveau/core/subdev/fb/gddr5.c
Simple merge

diff --cc drivers/gpu/drm/nouveau/core/subdev/fb/priv.h
Simple merge

diff --cc drivers/gpu/drm/nouveau/core/subdev/fb/ramnve0.c
Simple merge