Move the trace before we signal the scheduler fence and drop the
scheduler fence reference directly before we free the job.

v2: keep extra s_fence reference
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NLiu, Monk <Monk.Liu@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>