Let the CS module decide if we can fall back to VRAM or not.

v2: remove unintended change
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>