drm/amdgpu:use job* to replace voluntary

that way we can know which job cause hang and
can do per sched reset/recovery instead of all
sched.

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>