drm/qxl: use QXL_GEM_DOMAIN_SURFACE for dumb gem objects

dumb buffers are used as qxl surfaces, so allocate them as
QXL_GEM_DOMAIN_SURFACE.  Should usually be allocated in
PRIV ttm domain then, so this reduces VRAM memory pressure.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Acked-by: NNoralf Trønnes <noralf@tronnes.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20190118122020.27596-10-kraxel@redhat.com

drivers/gpu/drm/qxl/qxl_dumb.c

@@ -59,7 +59,7 @@ int qxl_mode_dumb_create(struct drm_file *file_priv,
 	surf.stride = pitch;
 	surf.format = format;
 	r = qxl_gem_object_create_with_handle(qdev, file_priv,
-					      QXL_GEM_DOMAIN_VRAM,
+					      QXL_GEM_DOMAIN_SURFACE,
 					      args->size, &surf, &qobj,
 					      &handle);
 	if (r)