We unmapped imported DMA-bufs when the GEM handle was dropped, not when the
hardware was done with the buffere.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NMichel Dänzer <michel.daenzer@amd.com>
CC: stable@vger.kernel.org
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>