drm/nouveau/disp: convert user classes to new-style nvkm_object

drivers/gpu/drm/nouveau/include/nvkm/core/oproxy.h

drivers/gpu/drm/nouveau/include/nvkm/engine/disp.h

drivers/gpu/drm/nouveau/nvkm/core/Kbuild

drivers/gpu/drm/nouveau/nvkm/core/oproxy.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/Kbuild

drivers/gpu/drm/nouveau/nvkm/engine/disp/base.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/baseg84.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/basegf119.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/basegk104.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/basegk110.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/basegt200.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/basegt215.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/basenv50.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.h

drivers/gpu/drm/nouveau/nvkm/engine/disp/coreg84.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/coreg94.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/coregf119.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/coregk104.c

drivers/gpu/drm/nouveau/nvkm/engine/disp/coregk110.c