drm/scheduler: signal scheduled fence when kill job

In the Linux kernel, the following vulnerability has been resolved:

drm/scheduler: signal scheduled fence when kill job

When an entity from application B is killed, drm_sched_entity_kill()

removes all jobs belonging to that entity through

drm_sched_entity_kill_jobs_work(). If application A's job depends on a

scheduled fence from application B's job, and that fence is not properly

signaled during the killing process, application A's dependency cannot be

cleared.

This leads to application A hanging indefinitely while waiting for a

dependency that will never be resolved. Fix this issue by ensuring that

scheduled fences are properly signaled when an entity is killed, allowing

dependent applications to continue execution.