drm/sched: fix timeout handling v2

We need to make sure that we don't race between job completion and
timeout.

v2: put revert label after calling the handling manually

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Nayan Deshmukh <nayan26deshmukh@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>