this can fix the memory leak under the case that not all
BO are freed during "takedown" stage, because originally
it blocks following kfree on mgr.
Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>